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Izuku had never been a cat person before. It always made him cry when the stray cat that lived behind his apartment would swat and hiss at him for trying to get too close. He’d been scratched once and could never get the courage to go up to the old tabby again.
(Though he did always ask his mama for a bowl of milk he could leave in the alley for him every morning.)
Izuku didn’t make many friends at school–too weird, the other kids would say–so he was used to playing in the park by himself. It’s how he found the hidden path to the woods that led to his house, just past the slides. He crawled under the hole in the fence. He was small enough to fit through without getting the metal caught in his clothes. Then Izuku was free to explore the whole woods without anyone making fun of him for his hair or his freckles or the way he talked or how he liked to talk and talk and talk and talk forever about all of his favorite things.
There was no one to stop him when he wanted to crouch down and watch the patterns the ants made in the dirt, or to take a minute to look at a pretty flower and try to find it in the book about flowers Mama got him for his birthday that summer, so he could try to match the picture to the flower and learn its name.
It was while he was looking at the nice blue ajisai that he heard a pitiful cry from deeper in the woods. Izuku, startled, fell back on his butt. He looked around him but couldn’t see anyone else around him besides the ants and the birds—oh, no, the birds flew away at the sound.
It came again, that sad and scared cry, sounding like the yowls the old tabby behind his apartment made sometimes.
Was there a kitty in trouble out here?
Izuku got to his feet, only just remembering to put his book back in his backpack before he ran to find the kitty. (His mama would be upset with him if he lost his new book already.) It didn’t make a sound again all the while that Izuku was running through the woods and that scared him. What if something had happened to this kitty? Was it hurt? Did it stop crying because it couldn’t cry anymore?
Tears were already welling up in Izuku’s eyes, thick and overflowing, dripping to the forest floor like rain. The sun was bright and hot above him. Finally, breaking through some bushes, he found the kitty. It’s a little orange striped thing, sort of like the old tabby behind his apartment but with darker stripes. Its eyes were closed and it's panting heavily; Izuku can see its ribs and he choked on a sob. The little cat’s eye opened and Izuku can barely see its red color through his tears.
“Oh kitty, poor cat-chan! Are you hurt?” Izuku stepped forward, cautiously. The cat raised its lips in a little growl, but no sound came out. It looked exhausted and too thin to be healthy. Its head fell back against the ground and it closed its eyes again. “I’m gonna help you, okay? Please don’t bite me little cat-chan, okay?”
The cat made a noise like a huff but didn’t react further when Izuku crouched down beside it. While its a little small, its paws were bigger and its tail was longer than Izuku had ever seen before. But he didn’t know as much about cats yet, so maybe this was just what sick cats look like.
He gently scooped the kitty into his arms and with all the strength his little four-year-old body had, picked it up and cradled it to his chest. The kitty made an irritated sounding grumble but fell limp in Izuku’s arms. Izuku had to carefully tuck him into his overalls so he didn’t drop the kitty as he ran straight through the woods to where it opened into the street by his apartment. He ran up the three flights of stairs, trying his best not to jostle the sleeping kitty.
Little Cat-chan was making little rumbly noises as Izuku clutched him to his chest. Cat-chan squirmed when Izuku pushed open the door to his house and went stumbling in, kicking off his shoes at the genkan before shouting for his mama.
“Mama, mama! I found a kitty! I think Cat-chan is hurt!” He wriggled Cat-chan out of his overalls to present it to Mama, who came running from the kitchen when Izuku had shouted. He held Cat-chan out to her.
Mama stopped right around the corner, eyes wide. The ladle in her hand dropped to the floor, the sound of it making Cat-chan yowl.
“Izuku! That’s not–”
“Mama, help him! He must be hurt, he’s so little! You make sick people feel better, so please!” Izuku cried, sniffling loudly and knowing he was dripping snot and tears all down his front. “Please help Cat-chan!”
Inko stood frozen for another moment, face white as a sheet, before the creature in her son’s arms mewled pitifully. Silently praying to the gods that this would be the right decision, she ushered her son and the not-a-cat into the apartment. She was a human nurse, only very rarely dealing with sick hybrids. What good could she do for a tiger cub ?
It turns out Kacchan (as Izuku had taken to calling him between sobs, unable to fully articulate the original nickname and the new one just stuck) had grown very attached to Izuku. He would let no one near him unless Izuku was the one holding him. He scratched the vet and her assistant until Izuku managed to pull him into his arms and soothe him. Kacchan went from a spitting little demon to a soft, purring kitty in Izuku’s hands.
Inko and the vet had no idea where Kacchan could have come from. The nearby zoo didn’t have any tiger cubs to lose and there were no known tiger hybrids in the area. Other than being malnourished and dehydrated, the vet found patches of irritated skin under Kacchan’s fur, on his neck and legs. Izuku cried when he saw them. Kacchan had clearly been kept by someone before Izuku found him, and it hurt Izuku’s young heart to see how easily someone could be hurt.
While the vet and Inko discussed Kacchan’s test results, Izuku clutched him close to his chest, pressing a kiss to his forehead the same way his Mama did when Izuku got scraped up. He sniffled. “I promise I’ll take care of you, Kacchan. Forever.”
Kacchan made a little chirping noise and went back to sleep.
Later that day, the police showed up at their apartment. She said she’d come to see Izuku. Immediately, tears sprang from his eyes.
“D-Did I do a bad thing? A-Am I in t-trouble?” Izuku sniffled, tears falling into Kacchan’s fur where he was curled up on Izuku’s lap. “Are you taking Kacchan away?”
The policewoman went to sit across the couch where Izuku sat. In a second, Kacchan was on his feet, lip curled back and teeth exposed. The fur along his spine stood on end.
“No, no, I’m not,” the policewoman said, putting her hands up in a gesture of peace. That seemed to calm Kacchan down enough that he could settle back into Izuku’s lap. However, he kept his narrowed red eyes firmly pinned to every move she made. “I’m just here to ask you some questions.”
Izuku clung to Kacchan uncertainly. When he nodded, the policewoman went on. She asked him where and when he’d found Kacchan, if there was anything or anyone else around. Things like if he’d seen anyone suspicious at the park, or if he heard anything unusual. While he answered, Kacchan licked his fingers. It felt a little strange, like something rough was rubbing against his skin, but it kept Izuku calm.
When the policewoman seemed like she asked all of her questions, Izuku asked, “So I can keep Kacchan?”
The policewoman looked at his Mama, who nodded imperceptibly.
“No one is going to take him away from you, Midoriya-kun,” the policewoman said. “He can stay.”
Izuku smile wobbled, but he thanked the policewoman and scooped up Kacchan so he could run to his room and show him all of his All Might stuff.
Izuku and Kacchan went everywhere together. Izuku had even tried to bring him to school with him a few times. How his teachers kept finding Kacchan tucked into Izuku’s jacket, he didn’t know. After the third time it happened, Mama and Sensei Chinen had to sit him down to tell him that animals were not allowed at school.
When Izuku pointed out the turtle in their room, both women had to suppress their sighs. Apparently, turtles and tigers weren’t the same. Izuku wanted to argue but his mama frowned at him.
“But I promised I’d take care of him,” Izuku told Mama the next morning, Kacchan still bundled in his jacket. Kacchan was just a little orange bump peeking out from between the buttons.
“I know, sweetie, but he can’t go to school with you,” Inko said. “But how about this? I’ll take good care of him while you’re away and I can tell you all about it when you come home?”
Izuku pondered on that, looking down at Kacchan’s head and scratching gently behind one of his fuzzy ears. “Is that okay, Kacchan?”
Kacchan grumbled something, huffing as he wriggled in the confines of Izuku’s jacket. Izuku gave him one more kiss on the head and put him down on the floor. Kacchan circled Izuku’s legs, wrapping his long tail around his ankle.
“Be good, Kacchan, okay?” Izuku pet his head. “Don’t eat my pillow again, please?”
Kacchan huffed in response.
“Mama, remember! He likes pork katsu the most! A-and make sure he gets scratches behind the ear and under his chin! He likes those the most too. Please don’t forget!”
“I’ll remember, sweetie.” Inko cupped her son’s face. “Now go on to school or you’ll be late.”
Izuku crouched beside Kacchan and gave him another kiss on the forehead. “I’ll be back, Kacchan. Okay?”
Kacchan chirped out a little mrowp and swiped his paw at Izuku’s leg, his claws catching on his pant leg. He looked up at Izuku, large red eyes swimming with something like panic and distress.
“Kacchan, I’ll be back before you know it, okay? I promise.”
Kacchan yowled and let go of Izuku’s leg, before stalking away to hide under the couch. Izuku went to school and couldn’t stop crying all day.
By the time Izuku made it to middle school, Kacchan had grown a lot . He’d gotten bulky, head nearly at Izuku’s shoulder. Izuku was the shortest in his class, but still. Kacchan could easily tower over any of his classmates, especially standing on his hind feet.
Kacchan still slept in Izuku’s bed; he’d never outgrown the habit. Maybe Izuku should have listened to his mother and enforced a separate bed for Kacchan, but he didn’t even mind that his entire bed sagged with the weight of a full grown tiger. It was like having his own furry, warm, weighted blanket.
Kacchan had a habit of pushing Izuku into the bed when he would stay up late, studying or rewatching his favorite All Might episodes. He’d drag him out of his seat and corral him over before nudging him with his giant head until Izuku fell back on the mattress. And before Izuku even had the chance to shimmy around, Kacchan was lying across him, heavy head resting on Izuku’s chest and tail swishing lazily through the air. He eventually would wrap that tail around one of Izuku’s legs or waist, just to have constant contact with him through the night.
Izuku always fell asleep so fast, listening to the rumbling snores and feeling Kacchan’s hot (sometimes stinky) breath wash over his face. It was his favorite place in the world.
Except for school, Kacchan rarely left his side. There were even times Kacchan would be waiting outside of the school when the last bell rang; he must have become pretty well known in the neighborhood to never have caused any amount of panic.
Whenever Izuku would talk about Kacchan at school, he’d be laughed at. No one believed he’d rescued a tiger and kept him at home as a pet. They called him all sorts of names, from the usual weirdo and freak and some even calling him Deku –as if he were worthless.
Izuku wasn’t expecting Kacchan to be waiting for him that first time. There was just screaming coming from the school yard and people running, pushing over one another to get back inside. Curious, Izuku tried to steal a glance outside. He couldn’t see through the throng of people trying to barricade the door. It wasn’t until someone shouted about a tiger that he burst forward, shoving through the crowd and pushing his way outside. A few senpais tried to grab him, to keep him from going outside, others called him a suicidal freak. Some of his classmates, the smarter ones at least, were watching silently, cogs turning in their heads.
Izuku strode down the front steps, the entire school watching in horrified silence as he approached the wall. He came to a stop, fists on his hips, and he looked up at Kacchan expectantly. The tiger didn’t even bother opening his eyes. It was only the twitch of his nose and the curl of his tail that told him Kacchan knew he was there.
“Kacchan!” Izuku called up. “Stop scaring them!”
Kacchan lifted his lip, baring a fang at him.
“Yes you are, don’t give me that.” Izuku tapped his foot. Kacchan unsheathed his claws and scratched at the stone wall in response.
Izuku sighed and cocked his head. “So, what, you came all the way here and you’re not gonna give me a kiss?”
One red eye peeked open at that, watching Izuku intently. Izuku smiled crookedly at him, waiting. Kacchan stood, stretching his limbs. Izuku wasn’t even finished with his, “Oooh, big stretch!” before Kacchan leaped down in the most amazing display of litheness. There was a muffled chorus of screams from the school, but Izuku ignored them.
Kacchan circled him, head pushing at him roughly, nearly knocking him over. Izuku dipped down to get a raspy tongue to the face, giggling all the while. Izuku returned the affection with a big, wet kiss to Kacchan’s jaw. The tiger grumbled, pleased.
At some point, one of his teachers had stormed outside, red in the face, his combover wildly disheveled.
“Mr. Midoriya! What is the meaning of this!” he shouted, though he didn’t leave the top step. So he could remain an arm’s length from the doors.
“This is Kacchan, he’s–”
Izuku was interrupted by a deep, earth-shaking snarl. Kacchan had curled around his legs, lowered himself like he was getting ready to attack, and opened his mouth in such a ferocious display like Izuku had never seen from him before.
“Kacchan!” Izuku scolded, crouching to wrap his arms around his head. “Stop! That’s my teacher!”
Kacchan relaxed minutely, lips still curled back and ears flat. He didn’t fully relax, not even when Izuku scratched him in his favorite places.
“Sensei, this is Kacchan, my tiger!” Izuku said. His teacher stared at him, eyes wide and face white as a sheet.
“That thing cannot be on this campus! Animal control is on their way now to subdue that creature! Now step away before it hurts you!”
“He’s not a thing! ” Izuku cried. “He’s Kacchan! He would never hurt me.”
Kacchan started up his snarling again, tail lashing threateningly behind him. He was shifting on his paws, like he were calculating how much power it would take to leap the distance from here to the front door. Izuku just clung to Kacchan, burying his face in his neck. Izuku’s breathing was ragged and cold raced down his limbs until he couldn’t feel his fingers or toes.
“Please Kacchan, calm down. They’re going to take you away.”
Kacchan seemed to understand the desperation in Izuku’s voice, because he settled down. He just curled protectively around Izuku, pushing him down to spread over his lap and keep him pinned to the ground. Izuku didn’t mind that at all. Having that heavy pressure helped keep him calm, barely staving off the panic attack building in his chest.
Police and animal control arrived a few moments later, surrounding Izuku and Kacchan with nets and long animal catcher poles. He even saw one of them pulling out what looked like needles or darts. Someone loaded up a gun. His breaths came in raggedly, wheezing. His chest felt tight, like no matter how much he tried to fill his lungs there just wasn’t enough air. He clung to Kacchan’s fur tighter, clinging to him with all of his might.
The police were trying to tell him something, but he couldn’t hear anything except for Kacchan’s growls. Izuku’s mother showed up at some point, talking hurriedly with the police and animal control, showing them some sort of paperwork, explaining something with frantic arm movements. Izuku buried his face in Kacchan’s neck and trembled. He wasn’t going to let anyone take Kacchan away, he wasn’t going to let anyone hurt him again.
Kacchan belonged at Izuku’s side, and nowhere else.
It took Kacchan nudging him with his paw for Izuku to come back up. He blinked the sunlight away, temporarily blinded. When his eyes adjusted, his mother was kneeling next to him.
“Izuku honey,” she said softly, petting through his hair. “It’s okay. I explained everything to them, the police, animal control, even your teachers. I didn’t know Kacchan left, I’m sorry.”
Izuku sniffled. “No, I shouldn’t have reacted like that. I just got so scared… They wanted to hurt him.”
Inko shook her head. “They wanted to make sure Kacchan wouldn’t hurt anyone.”
“But he wouldn’t! Kacchan has never hurt anyone!” Izuku said.
Inko frowned. “You may be used to him, baby, but not everyone is. They just see a tiger and think they’re in danger. Do you understand? They know about Kacchan now, so this shouldn’t happen again, but he can’t be on school property anymore. He’s not allowed.”
Izuku nodded. “Can we just go home please?”
Inko stood and Kacchan helped push Izuku to his feet. His mother began to walk away. Izuku stood motionless for a moment, looking over his shoulder at the school. The crowd gathered at the front door watched him silently. He couldn’t make out what their faces looked like, but he could imagine. Izuku must have struck some kind of figure, standing there with a tiger wrapped around his legs.
They didn’t call him a weirdo or a freak anymore. At least not to his face. And the few friends he’d started to make stopped talking to him all together. Everyone avoided him. No one wanted to be friends with the kid with a pet tiger. They were scared of him now. Scared of what that animal would do to them, as if Izuku would sic Kacchan on them for upsetting him.
It was fine, Izuku figured. He had Kacchan and that was all he needed anyway.
Kacchan was acting weird. Kacchan, for the most part, was not a pacer. He didn’t move anxiously about the apartment. He had always been a relaxed tiger, always dozing on the balcony or sprawled across Izuku’s bed.
But Kacchan was pacing back and forth, his tail lashing behind him, ears pulled flat. A constant whining grumble left his throat. He seemed irritated and no amount of scratching behind his ear seemed to ease him. Throughout the day, Kacchan would drag Izuku from his desk where he’d been studying and pin him to the floor, nuzzling his big head against his chest and lapping his tongue all around Izuku’s face and neck until he was dripping in tiger saliva. He didn’t ease up until he was satisfied—whatever that entailed—regardless of Izuku’s protests and attempts to push the giant cat off him.
It wasn’t unusual for Kacchan to bully him into taking a break (a cuddle), but the nuzzling and licking combined were new. Over the years, Izuku liked to think he’d read enough about tigers that he was somewhat of an expert on them. This behavior was abnormal for most tigers. They don’t really scent others this way. Though Kacchan wasn’t really a regular tiger. He was Kacchan, after all.
Maybe this was some tiger thing Izuku didn’t know about. Maybe Kacchan being raised domestically affected him like this, where he got a little clingy and felt the need to scent him. So Izuku just let the tiger do what he needed to do. He was going to take the best care of Kacchan, give him anything to make sure he was happy.
Kacchan walked him to and from school, Kacchan slept in his bed with him, Kacchan could get Izuku to do just about anything. He was wrapped around his big orange paw, and Izuku wouldn’t change a thing.
When Izuku got accepted into UA High School, their routine changed. Since UA was further away than his middle school, Kacchan couldn’t accompany him to the school gates anymore. The first time Izuku had to leave him behind at the train station—because No Kacchan, tigers can’t board the train, I’m sorry —Kacchan had practically thrown a tantrum. He yowled and hissed the whole time, fur bristling and tail lashing. And while he still showed up at the station when Izuku came home after classes, it was to a cold shoulder and a huffy Kacchan. He ignored Izuku for the rest of the night, opting to sleep elsewhere for the first time in many, many years.
It took a few days for Kacchan to get over it. There was a lot of aggressive scenting after that; Izuku walked around practically smelling like an animal himself. It seemed to bring a modicum of discomfort to his new classmates; some of which were hybrids!
There hadn’t been any hybrid students at Aldera Middle. Izuku never really knew why, but UA had a huge student population and it was fascinating to see all the different interactions happening all around him now. He’d even started making more friends! He wasn’t known as “the kid with the tiger” anymore. No one knew him from before, so they weren’t scared of him. Izuku may have been shy and a little too enthusiastic when meeting new people, but at least he was meeting them.
He loved Kacchan, he really truly did, but it had been a lonely experience growing up the way he did. It made it all too easy to be awkward and weird around new people now. He kept tripping over his words and his feet every time he came up to someone new. But his classmates seemed nice; they laughed but it wasn’t mean. They helped him stand and introduced themselves instead of making fun of him.
It was a refreshing change of pace.
The first person he met on campus had been a squirrel hybrid girl, who’d helped catch him when he tripped over his two left feet on the way up to the doors. Uraraka had been nice, with her little pointed ears and large fluffy tail. Her ears flicked up and down excitedly while they talked the entire walk to their homeroom. Her nose twitched and she frowned.
“Do you know any other hybrids, Midoriya-kun?” She asked, her fluffy tail straightening. “I thought maybe that smell was from some of the other hybrids but it’s you.”
“Oh!” Izuku flushed, hiding behind his arms. “You’re actually the first hybrid I’ve met. You must be smelling Kacchan.”
“Who’s that?”
“My best friend! Or rather… my tiger!” Izuku beamed. “I found him when I was a kid, he’d been hurt and left behind in the woods and we nursed him back to health. And Kacchan’s been living with us ever since.”
Uraraka’s face blanched, her hand shooting out to grip Izuku’s forearm. Her little claws dug into him, leaving little pinpricks of pain behind. “A tiger?! Do you mean a tiger hybrid? ”
“No, Kacchan’s just a regular tiger. The vet checked him and everything.”
Uraraka’s lips tightened into a deeper frown. “I’ve never known tigers to just be around like that. Shouldn’t he be in a zoo?”
“No! He’s a good boy, he’s just like an oversized house cat, really! When I found him, the police thought he might have escaped from a smuggling ring for exotic pets. I don’t know if they were ever caught, though.”
Uraraka’s brown eyes widened and just as she was about to open her mouth to say more, the warning bell chimed and they rushed inside to find their seats.
Izuku was amazed at the number of hybrids actually in their class. There was a sleepy cat boy sitting behind him, dark ears angled forward. A cute frog girl a few rows over, next to Uraraka, and even a blonde fox with a black lightning bolt stripe dyed into his ear fur! Izuku didn’t get a chance to spot any more, since their sensei walked in (a black cat hybrid! How cool!) and began his lecture without any preamble.
He couldn’t wait to meet everyone later!
Later that night, Izuku lay awake in bed, buzzing from his first day in school. Kacchan was still mad at him for having to leave him behind at the train station and was sleeping out on the couch. It was strange not to feel Kacchan’s heavy weight pressing him into the mattress, stranger still to not be able to talk to him about his day.
He mulled over Uraraka’s words before homeroom. Kacchan? A tiger hybrid? The thought was almost laughable. Surely he would have seen him change into his hybrid form over the past decade, wouldn’t he? He’d done some reading up on hybrids during a free period. They couldn’t stay in their animal form for too long at once; many hybrid accounts likened it to wearing the same clothes every day. At some point, it just becomes uncomfortable staying in one form over the other.
It was usually up to the hybrid themselves, but many changed at least once a day. Though Izuku figured it would be up to personal preference how often one would change their form.
If Kacchan were a hybrid, wouldn’t he have shown himself at some point? Izuku couldn’t help but wonder what he might look like as a human. Pretty, most likely, and confident. Kacchan always carried himself like he knew he was the best (regardless of how many times it was Izuku telling him so). Maybe he’d have a puff of spiky hair, like the fur around his neck. Big too, probably. Kacchan was a pretty big tiger, even for his age, and Izuku liked to imagine he’d be taller and broader than he was.
Something inside Izuku’s gut tightened, and he felt warmth pooling between his legs. Izuku shook himself, rubbing his hands vigorously down his face. No, no, what was he thinking! He shouldn’t be having these kinds of thoughts about Kacchan! He wasn’t a hybrid; Izuku would have known by now if he was. Kacchan was just a regular tiger, who lived in his third floor apartment building and walked him to and from school every day since he was a little kid.
That’s all he was. Nothing more, nothing less.
But why did some part of him, a tiny kernel in his heart, ache at the idea of Kacchan being able to talk back to him? Hold his hand? Look into his eyes and smile. What would it feel like to hear Kacchan say his name?
Izuku locked those thoughts away, deep inside, and rolled over to try and get some sleep. He wasn’t sure how he could without Kacchan there, but he’d have to try. There was probably going to be a point in his future where he’d have to get used to not having him at his side anymore.
Izuku fell asleep with tears in his eyes and a crack in his heart.
One winter’s night near the end of his third year, while a blizzard raged on outside their windows, Izuku didn’t feel a single bit of cold. Kacchan was sprawled over him, head on his chest and pressed all along his side, rumbling with his deep-throated tiger purrs. Izuku ran his fingers absentmindedly along his head, fingers finding all of Kacchan’s favorite spots to scratch.
He’d long since forgotten the notion that Kacchan could be a hybrid. Instead, Izuku was thinking too much about a tiger’s natural lifespan. They were quickly approaching the expected twenty years a tiger may live in captivity; sure they took good care of Kacchan, and he never seemed to go hungry or get sick, but Izuku still worried.
Kacchan grumbled softly, nudging his big head against Izuku’s palm. He blinked the tears in his eyes away, already knowing that Kacchan seemed to be worried about him right back.
“I’m okay, Kacchan,” Izuku murmured, rubbing his face with both hands now, digging his fingers into his fur and holding on. “I’m just… going to miss you.”
As if he understood, Kacchan made an incredulous mrowp noise and huffed indignantly. Kacchan really was just so smart. He always seemed to know what Izuku was saying.
Once again, Izuku found himself wondering what it might be like to hear Kacchan talk back for real. If Izuku had a superpower—like in those hero comics he loved—it would be to speak with animals. Maybe just Kacchan, even. All he wanted was to hear his deep voice rumbling back at him, responding to his questions, giving his input on everything.
Kacchan always had a bit of sass to him. He’d probably be snarky, teasing.
“You’re getting old, Kacchan.” Izuku sniffled. “I know it’s silly to hope you’d live forever, but it's just a fact of life that your lifespan is a lot shorter than mine.”
Izuku’s tears were starting to overflow, dampening his pillow. A sticky sob got stuck in Izuku’s throat.
“If I could give you half of my years so that we would never have to be without the other, I would. In a heartbeat. Faster than that, even.” Each word trembled as Izuku fought back the chest heaving sobs bubbling in his throat. “I don’t even know who I am without you, Kacchan. You’re my best friend, always.”
Kacchan shoved his head against Izuku’s, grinding their cheeks together and smothering the pain in Izuku’s heart. He grumbled low, tail wrapping tightly around his calf and a massive paw flopping over Izuku’s waist as if to hold him there. Kacchan ran his rough tongue over Izuku’s temple, getting his hair to stick up on end.
Izuku wrapped his arms around Kacchan’s big head and sobbed into his fur. As he slept, Izuku dreamed of big warm hands holding him close and a deep, rough voice whispering, “Stupid Izuku, I’m gonna be with you for the rest of our lives.”
It was shortly after the school year ended when Izuku presented as an omega. He was the last in his graduating class to present; everyone else had presented their secondary genders before second year. His mother said every Midoriya had been a late bloomer; she didn’t present until her college years too. His first heat was excruciating.
The pain was debilitating. His stomach cramped and squeezed all day and night. He couldn’t stomach any food and he was so feverish the whole time that he thought he’d sweat straight through his mattress. He burned so deeply, especially between his legs, that all he could do was whimper and whine. His inner omega howled endlessly. It wanted something but Izuku didn’t know what.
The worst part was that he wasn’t allowed to see Kacchan at all during his heat. The door remained firmly locked and only his mother ever came in, to give him water and try to get him to eat. Izuku missed his Kacchan so much that it hurt worse than the cramps and the aching need in his new omegan anatomy.
He could, however, smell Kacchan now. With his presentation, his new senses emerged. The tiger smelled so warm, like spiced chai and something a little sugary. He craved it, burying his face in anything of his that smelled like Kacchan. Why did he want that smell to infuse his very molecules? He needed it to be a part of him so badly that he couldn’t stop crying when the scent started to fade after going several days without Kacchan.
It got embarrassing very quickly. There were just some things he imagined during his heat that he never wanted to even think about in broad daylight. It twisted his gut with guilt and delicious need at the same time.
Izuku excelled at university; veterinary school felt like second nature to him. It excited him; everything he learned made him that much more enthusiastic to know more. He realized pretty early on that he wanted to be able to help those that couldn’t ask for it; pets of all sorts that needed to get better, and in a way also healing the hurt in their owner’s hearts too. To give them that relief of knowing their beloved companion is in good hands and can stay at their side for a little longer.
He had a vested interest in care for exotic animals too. Izuku could hear the very reason for that pacing on the other side of their apartment door. He smiled to himself as he opened the door, struggling to get through it when Kacchan pushed his giant head forward and into Izuku’s stomach. He grumbled deep from his chest, tail lashing.
“I missed you too, Kacchan.” Izuku laughed, scratching him behind the ears and slowly backing him up so Izuku could close the door. Kacchan chirped and pushed Izuku back into the wall, nuzzling into his hips. Kacchan always seemed a little grumpy when Izuku came home from school, especially on days he didn’t walk him to and from the train station.
Kacchan has always been possessive of Izuku, and had been for years, but it had gotten worse since Izuku had presented. The tiger never let an opportunity to scent Izuku pass him by. It was always the first thing he did when Izuku came home. He figured it was due to all the new animal scents lingering on him after his labs and practicals. Izuku didn’t mind; he loved when Kacchan was extra affectionate. And if he swiped his own wrist glands over Kacchan’s fur when he went to pet him, well, that was just his little secret.
Kacchan shoved his head bodily around Izuku, headbutting his stomach and nuzzling his hips. One push of his giant head and Izuku was knocked over, pressed into the ground while Kacchan pawed at him to get him to sit still. Izuku laughed, letting the tiger get his fill. Warm bubbles fluttered in his stomach as Kacchan swiped his big tongue along his cheek, lapping up his hair and slobbering all over his face.
“Kacchan!” Izuku scolded, though the effect was immediately negated thanks to his laughter. He loved the heavy weight pressing into him whenever Kacchan sprawled over him. He felt protected, safe. Like nothing could go wrong while he was there.
Kacchan didn’t slow down like he usually did by now. Instead, his big paw held Izuku’s hips down and he lapped at his neck, dangerously close to his scent gland. Izuku bit his lip to stifle the moan rising in his throat. His heart picked up, thundering against his rib cage, and Izuku tried to close his legs to squash the warmth pooling between them. He shouldn’t be feeling this good just from a scenting from his tiger.
Izuku gripped Kacchan’s neck fur and urged him back. He felt flushed in the face while Kacchan’s blistering red eyes stared at him intently.
“That’s enough, Kacchan,” Izuku fought to keep his voice even. “I’ve got to study. We can go sit on the couch?”
Kacchan huffed and gave one last defiant lick to Izuku’s face before trundling over to the living room. Izuku sighed, letting his head fall back against the hardwood. If he kept this up, he’d be in trouble for sure.
Izuku felt hazy, like he was floating through the air. His vision couldn’t seem to clear; there was just darkness around him and a heavy feeling in his stomach. Was he dreaming? He couldn’t really move, but he felt warm, safe. Kacchan’s distinct scent wafted in the air and Izuku purred.
There was a heat pooling in his gut, swirling low and simmering, waiting to flare. His entire body was flushed, moist with sweat. A stickiness coated his thighs; a different kind of wetness that he hadn’t experienced before seemed to spill from that pooling heat. He thought it would feel uncomfortable, but it felt good .
Izuku heard a chuff. He lifted his head enough to see Kacchan lying between his legs, bright red eyes flashing in the night. He licked his chops, tail curling behind him. Izuku smiled, suffused with happiness. He curled his fingers into his silky fur, cupping the tiger’s head in his palm.
“Good boy,” Izuku murmured.
A pang of hurt stabbed through his stomach, radiating through his spine. Kacchan huffed, digging his head deeper between Izuku’s thighs. He gasped as the movement rubbed something; Izuku felt like he’d been struck by lightning. Kacchan’s hot breath wafted over his thighs and he couldn’t hold back the deep-chested moan that spilled from his mouth.
Kacchan raised his head, eyes wide. His ears twitched, like he was listening for the noise to come again. It wasn’t until he lowered his head to nose into the seam at his hip that Izuku cried out again. Kacchan chuffed, seemingly pleased.
“Kacchan…” Izuku groaned, gripping Kacchan’s fur a little tighter. He didn’t want this dream to end.
In a blink of an eye, Izuku’s shorts were ripped away, exposing him to the air. He bucked his hips, squirming in reaction to the feeling of hot tiger breath steaming over his exposed sex. This had been perhaps the strangest change when he’d presented so late, the way his cock–which hadn’t been very large to begin with–shrank to become a little cocklet, his insides twisting until he had grown fuzzy lips and a velvety hole. Izuku, curious, only had a few scant moments alone to inspect himself when the transition had occurred, from beta to omega. Kacchan didn’t seem to want to leave his side after all that had happened and it had been just too weird to even think about exploring himself with his best friend right there.
But now, Izuku keened as Kacchan nosed closer to his cunt. Kacchan was so close… He’d long since accepted that he was some sort of freak who enjoyed the attention. Izuku would sometimes let Kacchan scent a little more, roughhouse a little harder, sprawl between his legs when they slept. It just felt so good .
Izuku felt a familiar rough tongue lick between his thighs. He couldn’t stop the moan even if he wanted to. It wasn’t unusual for Kacchan to lick him, but he’d never done it down there. Izuku felt all the blood rush to his cheeks as he squirmed when that wet tongue lapped at his folds again.
Once, he could pass off as an accident. But twice was deliberate.
Oh, this was going to be a very good dream.
Heat bubbled between his legs and Izuku could feel the slick pooling on his skin, anything not caught on Kacchan’s tongue dripped down to the mattress. Kacchan huffed noisily, nosing against Izuku’s straining cocklet. He whimpered, rolling his hips upwards to chase the sensation. Izuku looked down through half-lidded eyes and was entranced by the view.
Kacchan’s big head nestled between his thighs, piercing red eyes watching Izuku’s every move, following each shiver and twitch, pink tongue only occasionally peeking out over Izuku’s sex as it lapped from his hole to his cock. Every languid lick sent a moan rocking through Izuku’s chest. He wanted to cry from how good it felt.
He could indulge in this, since he was dreaming. There was nothing holding him back here from enjoying the attention his tiger gave him. Kacchan was just so special to him that Izuku wanted him every way he possibly could. The fire his tiger lit in him was like nothing he’d ever experienced before. Izuku could revel in Kacchan’s attention forever, every scenting and possessive curl of his body, the way he lounged across Izuku’s lap.
He loved Kacchan, and it was the knowledge that this feeling would only ever remain in his dreams that broke Izuku’s heart. Tears spilled freely down his cheeks and dampened the pillow under his head. Kacchan chirped, concerned, and raised his head. Izuku nearly wailed at the loss of sensation, but Kacchan was already crawling up his body to press his face against Izuku’s. His tears clumped in Kacchan’s whiskers.
“Kacchan…” Izuku murmured, wrapping his arms around his tiger’s head. His heavy weight was pleasant, grounding.
Izuku floated in that dream space, face buried in musky tiger fur, inhaling deeply. Something large and hot prodded his hip. Izuku bit his lip to contain his moan, imagining that thick cock breaching his dripping hole.
A dream, a dream, it’s only a dream… He thought miserably.
Kacchan bucked his hips, rubbing against Izuku’s sensitive lips, his cock rubbing against everything, skin tingling with the sensation of the hardness spreading his slick everywhere. Tears still in his eyes, Izuku hid away from the rest of the world in Kacchan’s fur, rolling his hips in tandem. His chest felt ready to break, but so did the coil of need and heat in his gut.
The feeling was just too good to stop and weep harder; Izuku thrust his hips up faster, more desperately. He was climbing to a peak he’d never reached before and the only reason he even could was because of Kacchan’s body sprawled over him.
Before he knew it, Izuku was muffling a scream into Kacchan’s fur, his cocklet twitching as he spilled over his stomach. Kacchan growled in his ear, the sound vibrating his bones and sending a shudder down his spine, before he felt something hot and sticky coat his cunt.
He never wanted this dream to end.
Kacchan lifted his head from where he’d been pressing against Izuku’s and crawled back enough that he could start lapping up the mess on Izuku’s stomach. Izuku felt boneless and floaty. The feeling of Kacchan’s rough tongue against his overheated skin was a balm, so soothing that Izuku fell into a dreamless state, mind hazy.
When he woke the next morning, he should have been more concerned at the wet patch on the sheets. He was no stranger to wet dreams recently, and he wasn’t surprised at the outcome, though usually he just ends up soiling his shorts. He must have kicked them off somehow during the night since he woke up bare-bottomed.
It didn’t occur to him until later the following night when the only sign of his sleep shorts he’d found was a strip of ripped fabric under his bed that maybe he should have been worried. That maybe his dream last night hadn’t been totally a dream.
Izuku’s next few nights were sleepless, and it was really starting to affect his coursework. Kacchan was restless too, constantly grumpy. Izuku couldn’t help but remember the sight of those predatorial red eyes watching him during that “dream” the other night. It was burned into his retinas and it was on the forefront of his mind nonstop.
Come Friday night, Izuku was nearly falling asleep standing up as he was putting away his coat and shoes when he got home from classes. There was a note on the table from his mother, saying she was working overnight but dinner was in the fridge for when he got hungry. He was more likely to fall asleep on his plate rather than actually eat it.
But Izuku couldn’t fall asleep. He’d been plagued by guilt and shame ever since that night. Every time he tried to close his eyes, he remembered the sensation of Kacchan’s tongue on him. He squeezed his thighs to try to get some relief, to ease that burn inside him. But it was never enough.
When Izuku turned around, he found Kacchan lounging on the couch, glaring at him. He’d been so grumpy, ever since that night. Had he been aware of what had happened? Kacchan had never gone through a rut that Izuku knew about, and didn’t seem to ever possess an instinct to breed before.
In between blinks, Kacchan had slid his lithe form onto the floor and stalked up to Izuku. With a rough grumble, the tiger butted his head against Izuku’s hips.
“Kacchan?”
Kacchan shoved his head at the same spot again, nearly bowling Izuku over.
“What’s wrong?”
His response was a low snarl. Kacchan wound his way around Izuku’s legs, making him stagger back a few steps. As it kept happening, he realized Kacchan was herding Izuku towards his room.
“What are you doing, Kacchan? I have schoolwork–”
A muted growl and a lift of Kacchan’s lips, flashing his large teeth, cut Izuku off.
Kacchan had never done something like that before. It shocked Izuku enough that Kacchan managed to shove him towards the bedroom. Izuku didn’t snap out of it until the back of his knees hit the bed and he tumbled backward.
“Kacchan! Stop that!”
But Kacchan didn’t stop. He crawled onto the bed gracefully, powerful muscles rippling under his golden orange fur. The bed creaked with their combined weight. Izuku scrambled back as far as he could until Kacchan was looming over him, jaw open and panting. His pupils were slits; almost entirely red as he watched Izuku carefully. He looked like he was on the prowl.
Izuku shivered. “Wh-What are you–”
Kacchan lifted his lip in a silent snarl, sides heaving. Izuku wasn’t scared – Kacchan wasn’t a threat, despite all the signs indicating otherwise. He trusted Kacchan with his life. He was a loyal cat, always had been. But Izuku had no idea what could be wrong; it’s not like Kacchan could just tell him.
Kacchan’s rough tongue lapped at Izuku’s stomach, pushing his shirt up to his chest. His tail lashed languidly behind him and Izuku was entranced by it for just a moment until a heavy paw forced him down flat onto the bed. When Izuku refocused his attention on Kacchan’s face, the strangest thing happened.
As Kacchan was crawling over his body, he started to change size. Izuku’s jaw fell open as he watched as Kacchan’s fur receded until there was warm, brown skin patterned with dark stripes up his arms and down a bare torso. Suddenly the paw on Izuku’s chest had turned into a hand – a human hand. It curled against Izuku’s chest, long claw-like nails scratching welts into his skin. That massive tiger head Izuku loved to cuddle turned into the most handsome face he’d ever seen before. Sharp cheekbones, burning red eyes, a strong jaw and fangs peeking out from pink lips. Two tiger ears pointed forward from within a mane of spiky golden hair and the tail that had so entranced Izuku lashed through the air behind him.
His tiger had just turned into a man!
A terribly, horribly, absolutely sexy man that made Izuku squeeze his legs together when that now familiar heat coiled in his gut. Izuku gasped, suddenly hit with an onslaught of strong pheromones; sweet caramel and the earthy musk Izuku had associated with Kacchan their whole lives. The man his tiger had turned into was an alpha .
“You’ve been avoiding me, Deku.” Kacchan (?!?!) growled, eyes narrowed. Izuku was hypnotized by the way his mouth moved. “And you haven’t been fucking sleeping. So you’re gonna fucking sleep before you hurt yourself. Got it?”
Izuku gaped breathlessly at him. He still couldn’t come to terms with the fact that his tiger wasn’t really a tiger– but a smoking hot guy!
“Oi,” Kacchan batted his hand against Izuku’s head. It was so achingly familiar – something Kacchan would do to get Izuku’s attention – that it made Izuku realize that no matter what, this was just his Kacchan. Man or tiger, he’d grown up with him, was his best friend.
“Wha–” Izuku stammered, refusing to blink in case all of this turned out to be a hallucination. He needed this to be real.
“Kacchan, you’re a person?! ” Izuku cried.
“Hybrid,” Kacchan rolled his eyes and huffed.
“This whole time?!”
Kacchan’s ears flicked. “Quit fuckin’ yelling. Are you gonna fucking sleep or do I have to make you?”
“W-Wait, wait, wait!” Izuku sat up, unaware of how Kacchan was basically sitting in his lap, pressed chest to chest. Izuku was so much more awake now than he had been before. “You kept this from me our entire lives?! Why didn’t you tell me?”
Kacchan’s cheeks flushed and he glared into the corner of the room. “You loved the tiger so much that it was just easier to keep quiet.”
“But hybrids can’t spend that much time in their animal form, it’s supposed to be really uncomfortable. Have you been making yourself uncomfortable because you thought I, what, liked the tiger more? Kacchan is Kacchan! No matter what!”
The pink on Kacchan’s cheeks darkened. “Shut the fuck up. What do you think I was doing while you were away at school all fucking day?”
“I dunno, sleeping! Being a menace to the neighborhood!” Izuku threw his hands up.
“Nah, Auntie homeschooled me. Kinda hard to take tests with big ol’ paws.”
“ MOM KNEW?!” Izuku shrieked. Kacchan slapped one of his hands (big, warm, so big even as a hybrid) over Izuku’s mouth.
“Quit fucking yelling.” He glared, ears pulled back.
“Bu-But I don’t understand.” Izuku said, muffled through Kacchan’s palm. “You could have told me at any point, you could have gone to school with me, we could have–”
Izuku blanched. He glared up at Kacchan and smacked him in the chest. “I was so anxious these last few years! I thought you were going to die soon!”
“The fuck!” Kacchan recoiled from the hit. “Why?!”
“Because tigers only live on average 18 years in captivity! It’s been two years of panic crying about you dying!”
Kacchan smirked. “Ain’t nothing average about me, nerd.”
He shifted in Izuku’s lap. Izuku’s eyes went wide in horror.
“Y-You’ve been… this whole time! Scenting and seeing me and I told you so many things and you were completely aware of what happened the other night!” Izuku’s voice reached a fever pitch.
It hadn’t been a dream. He’d been awake and Kacchan had licked him until he came and he’d been aware of it the whole time. Izuku felt like he was going to drop dead.
Kacchan’s smirk was nothing but pure sin.
“I’ve been smelling your arousal for years, Deku baby.” He ducked low to whisper in Izuku’s ear. His breath was hot, scorching, against his skin. “I know all your dirty secrets.”
Izuku cried, burying his face in his hands. “Just kill me now please! One good chomp on my skull should do it!”
Kacchan barked out a laugh and leaned away. Izuku missed his heat immediately.
“Not gonna do that, nerd.” Kacchan said. “I’m serious, you’re gonna run yourself into the fucking ground if you don’t get some sleep.”
“Well I can’t sleep now, Kacchan! I just found out my best friend is a hybrid! I have so many questions!”
Kacchan pressed his weight down onto Izuku’s lap, rolling his hips. Izuku’s hands flew out to grip his slim waist and groaned. It was only now that he realized that Kacchan was entirely naked. Izuku drooled at the sight of his big cock, thick and slightly barbed like a tiger’s. He slicked up involuntarily.
“Well, I can always make you.” Kacchan leaned in and dragged his fangs against Izuku’s neck. He keened and turned his head, baring his throat to Kacchan’s mouth. “I’m about to rut, and you’ve been on the edge of pre-heat for days now. It’s been all I could smell lately.”
Izuku blinked numbly at him.
“Could fuck you ‘til you pass out.”
Izuku squeaked. He’d only ever dreamed about having Kacchan that way, and never would he imagine him turning human and saying it so plainly like that. Izuku was going to combust.
Was he actually dreaming and just hadn’t realized it? Or did he get hit by a bus and this was his afterlife?
“You have been a part of my life just as long as I’ve been a part of yours,” Kacchan said, cupping Izuku’s cheek. He rubbed his thumb — there was a springiness to his fingertips, almost like paw pads — across Izuku’s cheek, his claws caught the tears Izuku hadn’t even realized had fallen. “Whatever you think this is, it’s so much more than that. It’s not the heat hormones or what-fucking-ever. You mean just as much to me as you’ve always said I meant to you.”
“You really understood everything I ever said to you.” Izuku said, chest tight. It had been so easy to tell Kacchan anything and everything than it was to tell a real person the same things.
“Course I did, dummy.” Kacchan leaned forward so their foreheads touched. “I don’t really do words but I want you to know–”
“I know, Kacchan.” Izuku looked up at him through his lashes. “I think I’ve always known.”
“You don’t even know what I was going to say.” Kacchan huffed with a roll of his eyes. His cheeks were pink and his ears flicked.
“But I know my Kacchan so well.”
“Dork.” Kacchan’s tail swayed back and forth lazily. Kacchan dipped forward and slotted their lips together. Izuku gaped for a moment, wide eyed, before tilting his head and deepening their kiss.
Kacchan was a ferocious kisser, biting at Izuku’s lip and tongue flicking out to soothe the sting. He rocked his hips in Izuku’s lap, their heats rubbing together in the most delicious of ways. Izuku was getting lightheaded from it all. He never wanted to stop; he held onto Kacchan’s hips tighter, fingers digging in. Kacchan ran his long, elegant fingers through Izuku’s curls, gripping hard enough to make Izuku moan.
Kacchan’s other hand fell to Izuku’s waist and rucked his shirt up so he could trail his fingers up a blazing path from his stomach to his nipples. Izuku didn’t hesitate to yank the shirt over his head and toss it across the room.
“Kacchan…” Izuku gasped wetly and his tiger followed the line of his jaw with biting kisses, skirting just past his scent gland and sinking into the meat of his shoulder. Izuku bucked, eyes rolling to the back of his head. Pleasure zinged through his limbs.
Kacchan took him by the hips and lowered him to lay flat on the bed. Izuku went, pliant, fingers weaving through his spiky mane. It was just as soft as Kacchan’s fur and Izuku reveled in it. Kacchan took his time kissing along Izuku’s torso, sucking his nipple until it stood peaked and red, a circle of teeth crowning it.
Kacchan shimmied off Izuku’s shorts before he could even notice he was doing it. He tucked his face between Izuku’s sex and his thigh, breathing deeply. Red eyes burned as he watched Izuku squirm. This was so hauntingly familiar but this time, Izuku knew it wasn’t a dream. It made his stomach twist into knots, felt heavy in his chest.
He wanted this so bad. He never thought he’d get this chance—to be intimate with someone—ever, in his life. Izuku figured he’d spend the rest of his life grieving the loss of his only love and never be able to make himself feel that way about anyone else.
But since Kacchan was a hybrid, his whole future just opened up. Tears spilled down the sides of his face, wetting the pillow beneath his head. He wasn’t sure if they were because of the pure relief he felt or the fact that Kacchan was once again eating him out with voracious focus. Izuku wasn’t sure if he liked this tongue more than Kacchan’s tiger tongue. The pleasure pooling in his gut built and built until he felt like he was standing on a precipice, ready to fall.
But Kacchan was pulling away, snatching that release from his hands. He was panting over Izuku’s groin, tongue lolling out and dripping saliva down his chin. Kacchan’s entire face was smeared with slick and spit, wet from the nose down. His eyes were slitted, looking just as much of a predator now as he had the other night. Izuku whimpered at the sight.
He gripped Izuku by the hips and hauled him so he was propped up on Kacchan’s knees, ass in the air and nearly bent in half. Kacchan dragged his fingers through Izuku’s slick and slathered it along the length of his thick cock. Izuku’s toes curled; his pussy lips fluttered in anticipation.
“Kacchan…” he breathed, unable to tear his gaze away, “Want it… please…”
Katsuki bared a fang and snarled, all animalistic. He rubbed his crown between Izuku’s folds before slowly pressing inside. Izuku bit back his moan as Kacchan’s bulbous, prickly head popped inside. He was so thick; would it even fit inside of him?
Kacchan stuffed him, inch by inch, slowly forcing the air out of Izuku’s lungs until his hips smacked against his ass. Izuku couldn’t breathe, could barely see through the static film over his eyes. He was so full of Kacchan that anything that had been Izuku was immediately converted into Kacchan’s only.
Izuku flailed his hands until he could reach around Kacchan’s neck, clinging tightly to him like he might become unmoored. Kacchan was panting hard, mouth agape and nostrils flaring. His entire face was red, his eyes wide and sightless. His tail slashed through the air behind him, ears flat to his head. They were equally overwhelmed.
Izuku wanted—no, needed—this to never end. He also needed Kacchan to move . So he locked his legs around Kacchan’s waist and shoved him forward so he could grind deeper inside his cunt. Kacchan seemed to break out of whatever spell he’d been under and pulled his hips back until just his cockhead remained inside. Izuku’s walls clenched around him, hanging to the barbs on his hot length, hoping to keep him there longer.
Kacchan gave him a devilish smirk and drove his hips forward in a powerful thrust. Izuku wailed. Kacchan pounded into him, setting a punishing pace, and Izuku just couldn’t get a lick of air inside his lungs; he gasped and panted and whined, keening so loud he was sure all of their neighbors would hear. They were the furthest thing on his mind; all he could think about was being split open on Kacchan’s cock.
Izuku’s cunt frothed with slick, the lewd squelch undercut with the rhythmic plap plap plap of Kacchan’s hips hitting against his ass. His breathless ah ah ah s were the only thing he could manage to get out of his mouth. The hand Kacchan had curled around his hip tightened; claws pierced skin, drawing blood. Neither of them noticed; Kacchan had fallen too deep into his rut to know much of anything outside of cunt cock omega breed while Izuku’s eyes had rolled into the back of his head and all he could think was cock cunt alpha claim .
Fur bristled under Izuku’s hands. He pried his eyes open just enough to see patches of fur explode down Kacchan’s skin, turning him more tiger. His fangs elongated, hands turning back into paws. The longer he fucked into Izuku, the more he seemed to lose control of himself, of his hybrid form. Something about that made Izuku’s chest puff with pride. He was the source of Kacchan losing his iron-clad control; he was the only one who could bring Kacchan’s wild side out to the forefront.
Kacchan’s hips stuttered, losing their rhythm. He was growing frantic, growling and chuffing and baring his fangs. Sinking them into Izuku’s shoulder, always so close to Izuku’s scent gland but never actually there. At some point, Kacchan had partially shifted; an elongated maw, paws and strong hind legs. So much more fur, growing damp and sticky from Izuku’s slick. Something thick and bulbous pressed against Izuku’s hole, insistent.
Knot. Alpha’s knot.
The little voice in his hindbrain had never been so loud before. It screamed and roared and thrashed; Izuku needed Kacchan’s knot, needed his spend filling him up, needed to feel that cock jump and kick inside him as they were tied together.
Izuku rolled his hips, bucking upwards, trying to force Kacchan deeper. He cried out, the first coherent words after so long of only breathless moans and wails.
“Kacchan! Alpha! Knot! Now! Now!” He wailed, digging his fingernails into Kacchan’s back. They were hardly enough to pierce through his thick fur and skin, but it got the message across. “Now, fill me up, knot me, breed me, alpha, alpha, alpha! ”
Kacchan let out a deep roar, vibrating through both of their bodies and snarling while he pinned Izuku into a mating press—knees next to his ears—and fucked so deep and hard that his knot popped in and out, stretching Izuku to the max. Eventually, Izuku managed to lock onto it, squeezing it tight, the barbs on Kacchan’s cock digging into his walls.
Izuku screamed. The sudden heat of Kacchan’s spend was overwhelming. It flooded his insides, his stomach bulging not just from Kacchan’s massive size, but also from the insane amount of cum filling his guts. Kacchan clung on tighter, pressing their sweaty, dirty bodies close, and kept up a constant growl as he emptied his balls.
They panted in tandem, heaving in great gulps of air and breathing in each other’s satisfied scents. Heat flared through Izuku’s body; his omega was satisfied for now, but he knew now that he was fully in his heat, it wouldn’t stay that way for long. While Kacchan lapped at Izuku’s flushed skin with steady licks of his rough tiger tongue, Izuku did his best to readjust his sheets into a nest. He’d started nesting the other day, but he hadn’t yet been satisfied in its construction. And everything they’d just done had completely destroyed whatever semblance of a nest there had been. He clawed at sheets and pillows, trying to bring them close and wrap them up in their safety.
But if Izuku was being honest, he never felt safer than he did underneath Kacchan. His bulk hid Izuku well, it was all encompassing and warm and everything Izuku wanted.
“Kacchan…” Izuku murmured, voice hoarse. Kacchan nuzzled into Izuku’s temple gently in response. Izuku’s eyes fluttered, and it was getting harder to keep them open.
“Sleep, omega.” Kacchan grumbled. He sounded rough, halfway between his hybrid and tiger form, deep with rut.
“Need’ta talk…” Izuku turned and snuggled into Kacchan’s embrace, “‘bout us…”
“Sleep.” Kacchan repeated with only the faint traces of a command.
Izuku was helpless to resist, already halfway to sleep. Besides, with them heatsharing, he’d have plenty of time with Kacchan over the next few days. Though how much of it would be spent talking was left to be seen.
They emerged from their (newly shared) den a few days later. Kacchan was puffed up in pride, as if he knew on some instinctual level that their heatsharing had been successful, that Izuku bore his pups already. Izuku wasn’t too sure, but he wasn’t on any sort of contraception (it’s not like he was going to fuck anyone else) and he was resolutely ignoring his satisfied and preening omega hindbrain.
Kacchan was standing in Izuku’s kitchen, bare save for a pair of borrowed underwear that left nothing to the imagination, the seams stretching over his large hips, tail curling at the tip. He was grumbling loudly (and fondly) about how he was tired of Izuku’s shit cooking and that he was going to make him the “best fucking dinner ever”. Izuku just sat on the couch, watching him work with wide, awe-filled eyes. Kacchan’s broad shoulders rippled with muscle at every movement.
His long forgotten phone, charging at the coffee table, pinged as it turned on. Then it kept pinging, vibrating so much it nearly toppled to the floor. Izuku snatched it before it could fall, grimacing at the twinge in his back, courtesy of Kacchan. He swiped away most of the notifications without a passing glance, fielded the messages from concerned friends and sending a retroactive heat leave to his professors for his absences before he tackled the dozens of messages and missed calls from his mother. Guilt gnawed at his gut over how long he’d left his mother to worry, each text more frantic than the last.
He had barely read through them when his phone lit up with a video call. His mother was calling. Izuku answered the call, eyes widening as he took in his reflection in the corner. He looked like he’d been mauled by a wild animal (which was sort of true). His hair was a frizzy mess, red bruises and teeth marks littered his neck so much so that he angled the phone so his mother couldn’t see the state of anything below the jaw.
“Izuku!” Inko cried, “I’d been worried sick! What happened–”
“Mom, it’s okay!” Izuku tried to calm her down. “I was.. Um, just in heat the last few days. My phone died.”
That seemed to settle his mother well enough. “Oh, well, I’m glad nothing horrible’s happened.”
Izuku gave her a weak smile. “I’d love to talk, Mom, but I need to go take care of a few—”
Something crashed behind him. Izuku startled, turning to look at what caused the commotion. Kacchan had opened a drawer and several of Izuku’s pans came tumbling out.
“Izuku! What was that?” His mother asked, worry lining her face again.
“Nothing! Just–”
“Shit, sorry, Auntie,” Kacchan gruffed, coming up behind Izuku— still half naked— and with the angle Izuku held his phone at, on complete display for his mother. Bites and scratches and bruises in plain view. Izuku burned with embarrassment. “Someone doesn’t know how to stack pots and pans.”
He ruffled Izuku’s hair playfully.
“Oh, Katsuki-kun!” Inko smiled. “It’s nice to see you again!”
Inko narrowed her eyes at them through the screen, clearly coming to some conclusion. All Izuku knew was the anxiety crawling over his body, settling him deep into the couch, making him want to sink through the floor and away from his mother’s scrutinizing gaze.
She beamed at them. “Oh good, it’s about time! Thank you for taking care of my boy, Katsuki-kun.”
Kacchan huffed a pleased noise and sauntered back to the kitchen, tail flicking to smack Izuku on the cheek.
Somehow through all of this, Izuku had forgotten that his mother had known Kacchan was a hybrid all along. “Mom! You knew this whole time?!” Izuku screeched. “Why didn’t you tell me?!”
“What?” Inko blinked, confused. “You… didn’t?”
Izuku gaped at his mother, jaw on the floor.
“Honey, I thought you knew too. I mean, there was no way I would have allowed an actual tiger to stay with us. I had all the paperwork drafted to take Katsuki in as a hybrid companion soon after you found him. What happened to his family was a tragedy and—”
Izuku couldn’t hear another word over the buzzing in his ears. Suddenly, things started to make sense. Why his schools stopped making a stink about Kacchan, why any time the police or animal control was involved Mom brought them some paperwork and they’d leave without a fight. Why his landlord hadn’t even blinked when he and Kacchan moved into their own apartment last year.
“This whole time…” Izuku said weakly, voice hoarse, “everyone knew about Kacchan and no one thought to double check that I knew too?”
“Well, you’re a smart cookie sweetie, I really thought you knew.”
“Mom! I didn’t–!” Izuku stammered, unable to get the words out. His brain was on a feedback loop, unable to comprehend it all.
“I love him Auntie, but sometimes he’s so thick.” Kacchan said, reappearing with two bowls of soup. There was some fish sizzling on the burner still, and the rice cooker beeped happily a second later.
Izuku twisted to look up at Kacchan with wide eyes.
“Kacchan loves me?” Izuku murmured, tears welling. “Like… loves me loves me?”
“Tch,” Kacchan huffed, turning his pinkening face away, fangs peeking through his scowl. “Dork.”
“Kacchan, I love you too!” Izuku wailed, dropping his phone on the couch to leap into Kacchan’s arms. It was forgotten immediately.
“‘Zuku, wait, I have hot soup…!” Kacchan shouted, before dropping the bowls to the floor and catching Izuku. “Idiot.”
Izuku didn’t care. He nuzzled into Kacchan’s neck, purring happily as their combined scents filled the room full of warmth and joy. Even Kacchan’s brief, stinging annoyance at the spilled soup was gone as soon as he wrapped his arms under Izuku to keep him steady.
“Course I do, ‘Zu.” Kacchan murmured into his cheek, chuffing. “Always have.”
“Kacchan, I’m so glad you weren’t a cat.” Izuku giggled.
Kacchan grumped, nipping a warning bite onto Izuku’s jaw. “I’ll show you cat!”
He carried Izuku towards the bedroom, the sound of his bare feet turning into the heavy padding of his paws as he walked.
“Wait, wait, Kacchan, you’re cooking!” Izuku wriggled against the iron-clad hold Kacchan had on him.
“Burner’s off.” Kacchan growled, his face slowly becoming more tiger-like.
“Kacchan!” Izuku cried, laughing as he clung on tighter around his neck, even as Kacchan bent forward, half-way through his transformation. There was barely anything human left in him by the time Kacchan pushed Izuku into their bed.
“I’ll give you cats ,” Kacchan huffed, tail lashing. “Give you all my cubs, see how you like it then!”
Izuku was breathless with laughter when Kacchan claimed his mouth with a searing kiss. Guess he could use one more day of his heat leave. Spend another full day with his Kacchan, together and happier than he’d ever been in his life.
Izuku really had become a cat person in the end.