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Katsuki had been mated to Shouto for almost six months now. They got married right after graduation, since both sets of parents thought it would be a good idea. Shouto was a highly regarded alpha and Katsuki, while a little untraditional, was still a well-placed omega in society thanks to his parents’ wealth and fashion industry influence.
They moved into the Todoroki mansion since both Katsuki and Shouto ended up getting along with Enji. The man had fucked up in the past - with both of them - but he’d repented and worked hard to be a better father and person in general. Their internship with Endeavor’s agency had gone well in their first year and they actually returned there every year after, though they dropped Deku somewhere along the way. Good riddance, that beta just got in the way and annoyed the shit out of Katsuki.
Obviously, after the wedding and generous gifts, they had enough money to move into their own place, but after living in the dorms for so long, Katsuki didn’t want another tiny apartment or something. He liked the size and grandeur of the Todoroki estate and felt safer there than anywhere else. It was the territory of the strongest, most virile alpha he’d ever met - Enji.
He fed Enji once a week since the alpha was now in his familial pack and it was no longer a painful ordeal. It had never been after that first time, actually, which the alpha had apologized for. The guy was nearly feral with thirst and a powerful alpha, so Katsuki had easily let it slide. He knew what alphas were like when they didn’t get their milk. Now, he cradled the massive alpha’s head and cooed at him as he fed. He traced over his scar and pet his spiky hair.
Shouto nursed almost every night, generally right before bed with both of them falling asleep immediately after. Sometimes Katsuki awoke to Shouto still suckling. He didn’t mind. He only fed two alphas now, so he had plenty of milk to go around.
They were both still sidekicks, of course. Shouto for his father and Katsuki for Miruko. They had another year or so before they could make the transition into fully fledged heroes of their own. At that time, Katsuki would probably join Endeavor’s agency and start making his way to number one. Even as sidekicks, he and Shouto were both on the leaderboard, but still buried in the higher numbers. Katsuki was determined to be top 10 faster than Hawks. He was only 19, but he had a fucking plan, alright?
And part of that plan was to have a kid before he stopped being a sidekick. He knew he wanted a family, he always had. And he also knew that he didn’t want to have to put his career on hold later to have one. Why not just have one now when he could step back from the fray more easily during the last few months? People didn’t watch sidekicks as closely, so he’d be able to have his kid and keep climbing the charts.
Shouto was in agreement of starting their family earlier. Shouto only wanted one kid and that was fine with Katsuki. He’d rather have more, but just one would be alright. He was an only child himself and knew that he’d definitely reaped benefits from it that Shouto hadn’t. He knew their kid would end up with a strong quirk too. Any of their three quirks would be good on its own, let alone some combination of them. Ice explosions? Fire bombs? There was no way their kid wouldn’t kick ass.
Because they were on deadline, Shouto fucked Katsuki whenever he asked for it. And the omega asked a lot. Katsuki had gone off birth control months ago, but he still wasn’t pregnant. He begged for a knot almost every night that they weren’t working the late shift, but it just wasn’t doing the job. So he went off his heat suppressants too. He didn’t tell Shouto though, since he hadn’t had a heat in so long and didn’t know when it would start or exactly how he’d feel. He just knew it was easier to get pregnant during a heat.
Two weeks after he’d stopped taking the suppressants, he still hadn’t started his heat. Maybe his body was just fucked from all the medication he’d pumped into it over the years. The doctor had said he was fertile though, so it didn’t make sense.
He’d wanted to surprise Shouto with his heat, but his body just wasn’t playing along.
After a night out drinking with his friends, Katsuki returned home horny as hell. He didn’t usually drink that much since he hated to feel out of control, but they were celebrating Kaminari and Jirou’s engagement, so he’d had plenty of shots and shit. None of them were even old enough to drink, but some senpais had provided the liquor and it was a house party anyway.
Shouto had worked that night and was now in the study talking to his father, but Katsuki just stood in the doorway and released some pheromones. Both alphas turned to him immediately and he gestured to Shouto and then drunkenly stumbled away down the hall. Shouto was there in an instant, looping an arm over his shoulders and helping him to their bedroom.
Instead of having sex right away though, Shouto merely stripped them both of their clothes and then started to suckle at the omega’s chest. Katsuki groaned and tried to entice the alpha to fuck him, but Shouto was perfectly happy nuzzling and drinking. The alpha often murmured about mommy’s milk and how good it tasted, which never bothered Katsuki. If anything, now it just spurred on his inner omega.
“Fuck me, alpha,” he whined as he shoved at his husband. “Give me a pup.”
Shouto slowly pulled away and sat back. The alpha stroked at his own cock until it was fully hard and then stuffed it into Katsuki’s dripping pussy with no preamble. They had sex so often lately that foreplay was often thrown right out the window. Katsuki didn’t care. He just wanted that damn knot to finally do its job.
Their bodies grinded against each other in the dark, both grabbing at the other desperately as the hormones took over. Shouto went back to drinking, moaning about how good mommy felt while Katsuki just chanted over and over for him to knot.
After only a few minutes, Shouto shuddered and forced his knot in with a grunt. Katsuki’s body quaked with orgasm, the walls of his pussy fluttering around the knot desperately. Please work, he begged silently. Work work work. If he didn’t get pregnant soon, his master plan wouldn’t work. It’d be too late and impact his pro hero debut, which he refused to have happen.
Since they had sex so regularly, the knot didn’t last long. As soon as it deflated, Shouto slipped out and rolled over. The alpha was asleep in seconds. Katsuki was still feeling worked up and horny though. He thought about rubbing one out, but decided to just go pee and then come back to bed.
He left the bathroom across the hall swaying a bit. Shit, he must’ve had more to drink than he thought. He was still pretty fucking buzzed and didn’t actually feel like sleeping just yet. Hearing the TV on in the living room, he padded towards it. He was only wearing one of Shouto’s old t-shirts and some panties, but whatever. The shirt went to his mid-thigh, so it was fine right? He wasn’t indecent or anything. At least that’s what his drunken mind told itself.
Perching on the far edge of the sectional, he stared at the TV. Enji was watching the late-night news. Since he’d been out drinking, Katsuki had missed everything that happened that evening so he decided to stay and watch for a bit. He was still feeling hot and bothered, but that was fine. Maybe by the time he finally crawled into bed, he could elbow Shouto awake and go for another round. For now, he’d just watch TV with his father-in-law and try to cool down a bit.
“Can’t sleep?” Enji asked from the oversized recliner.
“Mm.”
“Something wrong?”
Katsuki sighed and finally looked over at the alpha. He probably shouldn’t spill all his problems, but he didn’t exactly have a strong filter right now. And besides, Enji had four fucking kids. He must know what it was like to try for a baby.
“I wanna get pregnant,” he lamented. “But it’s just not happening and I don’t know what to do. I’ll be debuting next year and time’s fuckin’ running out.”
“How long have you two been trying?”
“Months!” he whined as he flopped down on the sectional dramatically.
“I see,” the alpha replied. “I’m surprised it’s taking that long. You’re both young and healthy.”
“I know, right? I’d do anything for a baby at this point,” he said with a sad laugh.
The news came back on and they both tuned back in. Nothing major had happened, but there was a villain attack at some bank. Heroes already had it handled. Enji was always on-call, but things rarely escalated enough to bring in the number one hero unless it was truly drastic. Sidekicks got called in all the time, though thankfully not tonight.
After the news anchors signed off, Katsuki started pushing himself upright. He wasn’t tired, but he was feeling frisky enough to try to convince Shouto to go for another round. As he stood up, his head swam and his abdomen cramped painfully. Fuck, had his stupid heat decided to start now?
Stumbling, he caught himself on the arm of the recliner. His vision was swimming, but he could tell Enji was looking at him. He could smell the powerful wave of pheromones pulsing from the alpha and he couldn’t help but remember the first time he’d fed Enji. It had been scary at the time, to be so utterly ravished and overpowered. But now his inner omega was eager for such a strong alpha to hold him again.
“Katsuki?” Enji rumbled in concern.
He could feel slick dripping down his thighs, body ready to go.
“Alpha,” he panted, looking up at Enji through his sweaty bangs.
Enji growled and reached out for him. Katsuki didn’t flinch or back away, instead he pressed forward. The alpha picked him up easily. In a matter of seconds, he was deposited on Enji’s wide lap. The scent of a dominant alpha was all over, making Katsuki’s head spin and his inner omega wail in desperation.
Brain foggy with heat and desire, he let his hips grind down against the alpha’s lap. He could feel the massive cock inside the man’s slacks. It was way bigger than Shouto’s. Katsuki’s inner omega salivated at the thought of the alpha’s knot. It had to be gigantic, right? And Enji wasn’t sleeping with anyone. Rei was living with Fuyumi, and had been for a couple years at this point. Enji had set them up in a nice little house and they all got together for holidays and stuff. Since Katsuki and Shouto had moved in, they’d found no evidence of the alpha having an affair or side piece or anything. Meaning that Enji’s knot would be nice and full. Potent. He mewled wantonly as the alpha’s arms wrapped around him and pulled him into a searing kiss.
After making out for several minutes, Katsuki started to whine and beg for more. He wanted more of the alpha. Anything the man was willing to give, he’d take it. Slowly, Enji edged up Katsuki’s shirt. Leaning away slightly, Katsuki tugged it off and over his head. The alpha immediately descended and started to kiss and nip at Katsuki’s chest. He still had some milk left, but that’s not what Enji was going for. The alpha was merely teasing Katsuki’s nipples and getting him even more worked up.
Bringing his arms down, Katsuki wrapped them around his father-in-law’s head. He had a single moment of doubt. This was wrong, this was cheating. He had a mate, but that mate smelled so much like Enji. Felt so much like Enji, only smaller. His inner omega bowed to Enji’s potent alpha pheromones just like it would have thousands of years ago, before modern society told you it was wrong to have sex with different alphas. He just wanted a baby. A strong baby. And he wanted it soon. Enji was a prime alpha specimen, one who was clearly fertile and could give him the baby Shouto couldn’t. Katsuki couldn’t wait, he needed to get pregnant in the next month or so or maybe never at all. This was his chance to have the pup and family he wanted so much. The one Shouto wanted too. And the baby would still have some of Shouto in them, which made it fine, right? Shouto would never have to know.
Tilting the alpha’s head up, Katsuki kissed Enji and gave himself entirely over to his heat.
It wasn’t long before Enji’s own shirt disappeared and then Katsuki’s panties were torn off and the alpha’s fingers started teasing at his clit. Katsuki gasped as a single, huge finger pressed inside.
“You’re barely even stretched,” the alpha noted. “Didn’t Shouto breed you?”
“He did,” Katsuki whined around the intrusion of a second finger prying him open.
“There’s barely any cum.”
“Mm. Need a real alpha.”
Enji’s nostrils released steam like some kind of cartoon bull even as those meaty fingers flexed and bent inside Katsuki’s pussy. Katsuki knew Enji didn’t like to hear anyone bad mouthing Shouto, or any of the Todoroki kids really. But while Katsuki loved Shouto, he could still admit that the alpha was lacking in a few areas. Like properly breeding and knotting his omega.
Those fingers inside him didn’t stop though, insistently curling in a come-hither motion that had Katsuki’s legs shaking and his nails digging into Enji’s shoulders. A hot thumb flicked at his clit and he muffled his scream against the alpha’s mouth as an orgasm rippled through him.
Slick and the last remnants of Shouto’s spend leaked down his bare legs as he shuddered in Enji’s arms. The man’s pants were a mess and Katsuki tugged at them, eager to remove the barrier between them. Enji chuckled and slipped his fingers out of Katsuki’s drooling pussy so he could remove his own pants. Katsuki held back a plaintive whine and instead repositioned his legs to balance his weight on the chair instead of the alpha. The navy slacks fell away followed by dark boxer briefs, revealing the most gigantic cock Katsuki had ever seen. Not even porn stars were hung like the number one hero and Katsuki couldn’t help but stare. It was long and thick, with a bright, angry head and mass of dark red hair at the base. The waft of heavy alpha pheromones he got from it made his inner omega howl.
“This alpha enough for you?” Enji taunted and Katsuki keened high and desperate in the back of his throat.
“Fuck me,” he babbled. “Please, alpha. Please fuck me. Give me your knot, I need it.”
“So desperate, omega,” Enji sighed, stroking at his cock and watching Katsuki shake and beg in his lap.
“Please! Fill me up, gimme a pup. Please, alpha. Need it.”
“Yeah? You want a pup that bad?”
“Yes! Please, alpha. Please please please. I want one, Daddy. So bad! I’ll be a good mommy, I promise.”
Enji growled and manhandled Katsuki closer and lifted him up. He went easily, eyes finally leaving the alpha’s cock to look up at those blue eyes so bright they seemed to glow with an inner fire all their own.
“Daddy, hm?” the alpha crooned. “I like the sound of that.”
Katsuki was about to launch into another frantic tirade of begging fueled by his inner omega’s desperate heat-driven lust, but every word he knew flew out the window when the head of that huge cock pressed against his sloppy entrance. Oh god. It was so big, would it even fit?
“It will,” Enji promised.
The alpha’s hips rocked up and that cock forced itself several inches inside, squeezing past his tight rim and then sliding against his walls. It was a lot to handle and he grasped for the alpha’s shoulders again, holding on for dear life. He cried out as the dick sank deeper. Two wet fingers were promptly shoved into his mouth, quieting him down as he sucked his own slick off them. He could feel himself steadily being impaled on the massive cock below and sighed in dazed contentment when he finally reached the bottom and found his ass on Enji’s lap once more.
Kissing at the omega’s neck, Enji started up a slow rhythm. Barely even pulling his dick out a few inches before surging back inside smoothly. Katsuki choked at the sensation of being so deeply penetrated and moaned around the alpha’s thick fingers. His inner omega was delirious with pleasure and only craved more and more, causing his hips to wiggle and gyrate on the huge cock.
Enji finally rocked up into him harder, bouncing the omega on his dick. Katsuki held on for dear life and panted and groaned aloud when the alpha’s fingers slid out of his mouth. Enji gripped tightly at his waist instead, fingers easily meeting in the middle and pressing down on the slight protrusion in Katsuki’s abdomen from the alpha’s cock. Katsuki whined for more more more and deeper, always deeper.
Reduced to sobs and incoherent begging, Katsuki bounced up and down on the alpha’s cock. Delirious in his heat, he wasn’t even trying to be sexy or do a good job. He just wanted that knot. He delighted every time the alpha’s cock kissed at his cervix, promising a direct deposit of seed.
Yelping in surprise when the alpha suddenly stood up, Katsuki clung to Enji as the man fucked up into him even as he walked over to the couch. The alpha’s cock slipped free as Katsuki was laid down like something precious and Katsuki wailed.
“No! Need it! Put it back,” he grunted as he reached for the alpha in desperation. “Daddy, please!”
“Daddy’s here,” Enji soothed as he crawled over the omega.
Before he could complain more, Katsuki moaned as that cock pierced him again. In a better position now, the alpha started fucking him harder and deeper. Katsuki screamed and wrapped his legs around the alpha’s waist - or tried to, the guy was fucking massive - to keep him in place this time. He also grabbed at the alpha’s back, leaving scratch marks as he struggled to hold on. Enji’s pace was brutal and the sound of wet suction and heavy balls slapping on skin was loud. Good thing Shouto was far off down the hall and slept like the fucking dead.
Not that Katsuki had more than a spare thought for Shouto. Not when Enji was railing him within an inch of his life, that cock carving up his insides like he’d never experienced before. He could feel the swelling of the alpha’s knot too as it tugged at his entrance with each new thrust. Soon, soon he’d have it. Soon he’d be pregnant.
The idea filled him with desire and he grabbed for the alpha’s head and pulled him down into a messy kiss. Nails digging into Enji’s scalp, he bucked his own hips along with the rhythm as much as he could. Enji was so strong though, it was hard. And the alpha was holding him down, one meaty hand on his hip and the other groping at his chest. Milk was seeping out, but Katsuki didn’t care. Not when he was so close to getting what he wanted.
“Oh fuck, here it comes,” Enji groaned and Katsuki threw his head back.
With one final press, the enormous knot finally popped inside and Katsuki shrieked as his own orgasm hit him like a ton of bricks. Every nerve ending lit up and he arched his back, pressing his chest into the alpha above him, toes curling and legs shaking as he came. His pussy squeezed at the knot desperately, milking it of cum that felt like fucking lava erupting inside him. It was so deep and there was so fucking much of it. He was purring and crying at the same time, his inner omega singing in delight.
Enji sucked at the mating bite on the omega’s neck and Katsuki hummed and tilted his head to the side to give even more access. The alpha’s hips were still moving slightly, forcing that knot ever deeper. Katsuki gave a watery cry as his body spasmed again, the pressure on his g-spot milking another orgasm out of him.
“Pup me, pup me,” he muttered. “Please Daddy.”
“Shh. Daddy’s breeding you right now. Filling you up just how you deserve,” Enji whispered lowly into his ear. “You’re such a perfect omega. So tight and wet for Daddy. Such a good mommy.”
Purring, Katsuki nodded and cradled Enji’s head in his arms. He could feel every spurt of hot cum hitting his insides. Every few seconds there was another gush and he wiggled and moaned with each one. Enji shuffled down and lapped at the omega’s wet, messy chest. Katsuki trilled in delight when the alpha suckled a bit. Nothing was better than a knot in your pussy and a mouth on your tit, at least as far as Katsuki was concerned.
After a few minutes, the cum was still coming in steady, if slightly slower, bursts. Having the massive alpha on top of him was becoming difficult and Katsuki was sweaty and finding it hard to breathe. When his wiggling started to intensify, Enji finally popped off the omega’s nipple and rolled them over. Katsuki lay on top of the alpha, limbs draped over Enji and the couch lazily. He couldn’t move. He could barely even feel his legs. His core was so hot from cum and their earlier activities that he was sweating like crazy. He didn’t even care though. He got what he wanted. Was still getting it. He felt safe and sated as he nuzzled into the alpha’s hairy chest and breathed in those potent pheromones.
The knot lasted forever, pumping him full of thick alpha cum. When it finally deflated, Enji shifted and pulled out. Katsuki whined and scrambled to move his hands down, wanting to keep the cum inside.
“Don’t worry,” Enji laughed. “Daddy’s seed is strong, omega. It’ll take.
Relaxing a bit, Katsuki moved his hands away and instead looked down at his pussy. It was bright red and leaking profusely. He trusted Enji though. Why shouldn’t he? The alpha had gotten Rei pregnant at least four times. And omegas were incredibly fertile while in heat.
“C’mon, let’s not make a mess,” Enji said as he stood and then scooped Katsuki into his arms.
Letting out a surprised little yelp, Katsuki clung to the alpha as he was brought into the master bedroom and then the attached bathroom. He’d never been in there before, but it was spacious and featured a fancy walk-in glass shower.
Enji stepped inside the shower and the walls steamed over the second the water turned on due to the alpha’s presence. Enji washed the omega first and didn’t put Katsuki down until he could assure the alpha that his legs were functioning again. He helped wash the alpha’s back, but otherwise he was mostly doted upon and handled gently. He wanted to complain while the alpha scooped out some of the cum and slick, but he didn’t. No doubt Enji’s seed had already done its job.
Once clean, Enji dried them both off with warm towels and then carried Katsuki back into the living room. Shouto’s t-shirt was pulled on over Katsuki’s head, though the panties were long gone. Torn and then incinerated, no doubt. Enji dressed himself and then brought Katsuki to the hallway leading to his and Shouto’s bedroom.
“Go to bed,” Enji instructed with a little slap on the omega’s ass.
“Tch.”
His heat momentarily sated and his skin no longer smelling like Enji or sex, Katsuki started off towards his room. His inner omega was quietly purring away and he felt tired and happy. He’d sleep well tonight, that was for damn sure.
Katsuki stopped halfway down the hall and turned back.
“What if I’m not pregnant?” he asked, resting his hand on his stomach.
Enji grinned and stalked towards him. After a long, passionate kiss, the alpha patted his head.
“You can come to Daddy anytime and we can try again,” Enji whispered hotly next to his ear. “Daddy will give you all the pups you want.”
Blushing as more slick leaked out, he ducked his head and slipped away from the alpha. Sneaking back into his own bedroom, he closed the door softly and then crawled back into bed with Shouto. He should feel bad, he realized now that his heat was momentarily sated, but he didn’t. He did what he had to do to give them the family they both wanted.
Shouto stirred and reached for him. Katsuki hushed his mate and allowed Shouto to drink a bit. It wasn’t long before the alpha fell asleep on Katsuki’s exposed chest. With a little sigh, he pet at Shouto’s soft hair and wondered what the pup was going to look like. Red eyes or blue? Red hair or blond? A fiesty alpha brat or a fiery little omega? Regardless of what they looked like or what their secondary gender was, he knew that they’d have a strong quirk. That they’d become a great hero just like their mommy and daddy.
He decided to take a pregnancy test in a few days. They had ones now that were super sensitive and could accurately tell pretty quickly. In the meantime though, he planned to take Enji up on his offer to keep him full and satisfied. By the end of his heat, he’d have a pup for sure.
Katsuki emailed work to let them know he was taking a few days off. He’d wanted the heat to be a surprise, that’s why he hadn’t told Shouto about stopping his suppressants. It was supposed to be a way to reinvigorate their sex life since trying for a baby had put so much added pressure on Shouto’s shoulders. But now he could spend all day getting pupped by Enji and then snuggle with Shouto all night when his heat had been sated and his pheromones evened out. They’d still have sex if they wanted, of course, but they wouldn’t have to. Shouto didn’t know what his heats were like, so Katsuki could just pass it off as being lucky to have easy ones. After he had the baby, he’d just go right back on the medication and no one would ever have to know.
He fell asleep dreaming of the nest he’d build for them tomorrow with all the fancy blankets and linen in the house. Shouto would like that.
Fourteen weeks later, Katsuki laid on the little medical bed at his ultrasound appointment. His stomach was exposed, already nicely rounded and protruding. Shouto was by his side, squeezing his hand anxiously.
“Oh my, this is such exciting news!” the nurse exclaimed. “You’re having triplets!”
Shouto turned to look at Katsuki, eyes bugged out and mouth slack. Katsuki barked out a laugh. He didn’t know whether to thank the heat, Enji’s seed, or his own bull-headed determination to start a family before he launched his solo hero career. Three kids all at once? It was a dream come true.
“I wonder who they’ll look like,” the nurse mused as she printed out some pictures and handed them to a shell-shocked Shouto.
“Their daddy,” Katsuki replied with a grin.