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Nabateans, the original inhabitants of Fodlan. It is said Sothis blessed them with all the spoils of the land, but cursed their wombs to be barren, if not for a special time known as Dioghras, in which Nabatean women are overcome with the urge to mate once a full moon cycle. If they do not choose a mate during this time, they shall perish.
_
“Felix! Sylvain! Please, come quickly!” Seteth yelled, running down the entrance hall.
“Woah, Seteth,” Sylvain said, “What’s got you in such a rush?” Felix cocked an eyebrow at the green-haired man.
“It’s Professor Byleth. She’s…”
Fingernails sharpened into claws, teeth into fangs.
“Has she fallen ill?” Sylvain asked, concern in his voice.
“No, she’s...it’s hard to explain. Please, come with me. She’s locked herself in the Archbishop’s quarters and refuses to come out.”
Scales the color of falling snow covered her skin. Sharp horns protruding defiantly on the crown of her head.
Seteth walked both men to the third floor, silent as he climbed the stairs. The sound of their footsteps echoed throughout the stairwell, accenting the tense situation. Sylvain and Felix shared a glance, coming to an unspoken understanding with a nod. “Enough secrecy, old man. Is something wrong with the Professor?” Felix asked.
“Do you both remember when Professor Byleth was sucked into the darkness of Zaharas five years ago? How her hair and eyes changed?” Seteth asked as the men reached the outside of the archbishop chambers. Suddenly, a sharp, snake-like hiss erupted from behind the chamber doors, causing Sylvain to jump in fright.
“Hard to forget when your Professor comes out of a supposedly impenetrable spell looking, well, green,” Felix replied dryly, unfazed. “So, is this a side effect from all that?”
Seteth sighed. “In a way. To tell you both the truth...your Professor has been very special from the beginning. The heart of the Goddess lies within her, and, we hypothesize, that connection to the Goddess allowed her to escape.”
“So, in other words,” Sylvain started, still eyeing the door suspiciously, “our Professor, like, merged with the Goddess? So...she’s part God? ”
“Not God, no. Her fusion with the Goddess means she joins Rhea, Flayn, and myself as one of the last living Nabateans. Unfortunately, that means dealing with certain...issues.”
Short wings, prehensile tail, a loud cry to the heavens above.
At the sound of their Professor’s inhuman wail, Sylvain and Felix nervously eyed Seteth, unsure of the extent of Byleth’s circumstances.
“...Like what? Stop dodging the question. It’s obviously important, or you wouldn’t have been in such a tizzy,” Felix said.
“Byleth is experiencing an ancient Nabatean cycle that comes every twelve moons. Normally, our kind are near infertile, but on this day female Nabateans are much more able to conceive children. What your Professor is experiencing right now can only be described as a ‘heat,’” Seteth said. “But, since her body was in stasis for five years, it was never able to complete the cycle. Therefore, your Professor is experiencing her first Nabatean Dioghras cycle, but at five times its normal strength.”
Sylvain and Felix paused, taking in all the information they’d learned. It was Felix who spoke first, “So why involve us? Sounds like she just needs a long day to herself.”
“I wish it were that simple, Felix. However, Nabateans who cannot find a mate during their cycle will die.”
“So you came to us?” Felix growled.
“You two are the only ones I could come to. Ashe is too shy, Dedue is dead, Dimitri is...and she needs sperm to sate the heat. It has to be one of you.”
A deafening roar shook the walls around the three men, Felix and Sylvain’s heads snapping to the shuttered doors of the archbishop chamber. If they focused, a sound almost like claws scraping on wood could be heard, sending alarm bells ringing in Felix’s head. Sylvain, however...
“I’ll do it,” Sylvain said.
“Thank you, Sylvain. For all of our sakes,” Seteth said.
“Of course you would. You don’t care about our Professor. You just want to get your dick wet,” Felix spat.
“Hey, listen, it’s either you or me! From the sound of it, she needs stamina. Of the two of us, I am the more experienced lover. I’m the natural choice,” Sylvain winked.
Felix rolled his eyes. “Just get this over with, Sylvain. Don’t fuck up. And, be careful. She doesn’t quite sound like herself,” Felix nervously listened back in, hearing the swish-swish of a large object on the floor.
“Awwe, it’s sweet you care, babe. Don’t worry about me, though. As they say, nothing bad ever happens to the Gautiers,” Sylvain said, waltzing into the Archbishop’s quarters and shutting the door.
Pitch black invaded Sylvain’s senses almost immediately, the setting afternoon sun illuminating deep claw marks on the wall and floor in flashes. Sylvain gulped, surveying the surroundings, inhaling softly when he spotted two green orbs peering at him through the darkness.
“Professor? Is that you?” Byleth shuffled further into the pseudo-nest she’d constructed in the corner of the room, all but her eyes covered by blankets.
“Go away, Sylvain! I need to be alone,” Byleth growled, her voice slightly distorted. It was something otherworldly, something feral, something beastly.
“Well, I can’t quite do that Professor. You’ll die if I don’t do something about it. Now, let’s just get you out of that blanket…” Sylvain reached down, and Byleth snarled , teeth snapping shut inches away from Sylvain’s hand.
“No! Leave, now!” Byleth roared, burying herself further into her nest. Sylvain only caught a glimpse of her for a second, but was shocked to see his Professor’s face covered in scales and crowned with horns.
Seteth really skimped on the details, he realized.
“Alright. I’ll leave, Professor. But, mark my words, we will not let you die tonight,” Sylvain said, heading back towards the door. “In fact, I think I know who might be able to get through to you.”
Closing the door behind him, Sylvain was immediately met with hurried questions from Felix and Seteth. “So, whore, did you do it? You were only in there for a couple of minutes, so probably not.”
“No, I didn’t. She obviously didn’t want to, and I wasn’t about to force myself on her,” Sylvain replied, his tone serious. That gave Felix alarm - Sylvain was only ever serious when the circumstances were really bad.
“So, Felix, will you try to-” Seteth started.
“Why didn’t you tell me she was a dragon, Seteth?” Sylvain interjected.
“I...assumed it wouldn’t be an issue,” Seteth admitted.
“She almost bit my hand off!”
“This might be a problem,” Felix said. “Before you continue trying to ask me, it’s a no. I can’t quite swing a sword with one hand.”
“Then, who’s going to save the Professor? I can try asking Ashe, maybe-”
“Nah, I got you covered. I know exactly who can get through to her. It’s going to take someone stubborn, someone tenacious, someone...sturdy.”
“What are you on about, Sylvain?” Felix eyed him disdainfully, yet knew exactly who Sylvain was referring to.
“You know exactly who, babe. It has to be His Highness! Dimitri can do it,” Sylvain announced triumphantly.
“He’d never agree to it,” Felix replied, “The boar’s too far gone to care for any life but his own.”
“Ok, ok, hear me out. First of all, Dimitri really, really wants to kill Edelgard, right? We can’t do that without the Professor. In fact, without her tactics, we’ll probably lose the war. He’ll have no choice. And, secondly, you can’t deny he had a massive crush on her back at the academy. I doubt it ever faded, honestly. Maybe we can use that?” Sylvain shrugged, looking pleased with his logic.
“Well, it’s worth an attempt. I do agree - I don’t think this war is winnable without Byleth. Perhaps he’ll listen to reason,” Seteth agreed.
Felix sighed. “Fine. I saw the boar brooding in the cathedral earlier, like always.”
Arriving at the cathedral, the trio was greeted with the familiar sight of Dimitri’s back, him brooding as much as ever. Felix could hear some students undergoing choir practice, and cursed them for daring to sing at such a time. Above, wyverns and pegasi made their rounds, wings audibly flapping through the hole in the roof.
“Dimitri! My old friend. I need a teensy little favor,” Sylvain said, clapping his hand on Dimitri’s cloak.
“Go away.”
“Well, that’s the second time I’ve been told that today,” Sylvain mused.
“Professor Byleth is going through a heat cycle right now, Dimitri,” Seteth pleaded, “I’ll spare you the details, but she needs for it to be sated, otherwise she’ll die. Will you help?”
That gave him pause. Byleth, dying?
Good riddance, spat Patricia. She only got in the way of your true goal.
I agree, replied Lambert. It’s better if you have fewer distractions, son.
She should’ve never climbed out of that damn hole, Glenn added.
“...no,” Dimitri replied, a hint of sadness in his voice.
“If she dies, you damn boar, we’re not going to win this war. Like it or not, we need her, or else you’ll never get to hang Edelgard’s head from the gates of Enbarr. That’s what you want, right?”
For once, the voices grew silent.
“I’ll do it.”
_
The door slammed shut as Dimitri stomped into the pitch black chamber, spotting Byleth’s glowing eyes in her blanket nest in the corner of the room. He snarled, huffing over to her, watching as her eyes squinted in fear? anger? apprehension?
Arousal?
“Go away, Dimitri,” Byleth growled, swatting her tail at his ankle.
“No. They sent me here to help you,” Dimitri said flatly, disinterest lining his voice.
“I said, leave. I don’t want to have to hurt you,” Byleth replied, baring her fangs.
“I’m not leaving until you’re over this,” Dimitri kneeled down, singular eye meeting her slitted green orbs.
“Didn’t you say you’d use me until the flesh fell from my bones?” Byleth snarled, “Where’s this sudden concern coming from?”
“If you die, I can’t kill that woman. That’s all this is. Nothing more,” Dimitri growled, a hint of insincerity in his tone.
“Get out, Dimitri!” Byleth cried. Dimitri extended his hands, cupping her face roughly. Their eyes met, Byleth snarling, Dimitri scowling.
“I will break you.”
The flames of the chamber alight with a brilliant fwoosh , filling the room with an almost ethereal purple glow. Byleth growled, rising from her nest, tackling Dimitri to the bed in one fluid motion. Her tongue hung loosely as she tore off his clothing, shreds of fabric and thread and fur torn to bits instantly by her sharpened claws.
She kissed him, all teeth and no finesse, gripping, clawing at his exposed skin till small droplets of red painted his arms. Her slick folds ground mercilessly on his stirring cock, Byleth moaning shamelessly as the head slipped inside her for a mere second. Dimitri gasped, taken aback by Byleth’s shameless display, and watched as she impaled herself on his cock with one languid thrust.
“Fuck, Dimitri...I don’t know what came over me…” Byleth moaned, fondling her left nipple in unpracticed circles, claw thumbing over the tip, “I’m gonna fuck you dry. ”
Byleth groaned as she slammed down on Dimitri’s cock again, and again, and again, gaining speed and going deeper and thrusting harder and harder until she came with a scream, wings unfolding, pillars of fire shooting up from the torches in the room.
And with only seconds of rest, Byleth began impaling herself again, tongue lolling out, speed and force no different than earlier. Dimitri swore he could see little hearts in her eyes as he fucked, no, more accurately, as she fucked herself on him.
“Slut. I can’t believe how desperate you are for my cock. I’m going to breed a little bastard into you, aren’t I?” Dimitri expected some reaction from Byleth after her degradation, but she barely heard him, too drunk on lust and cock and sex.
Byleth threw her head back in a moan as she hit her peak again, wings spread out and violet fire dancing in the room. A spray of slick coated Dimitri’s stomach, and he groaned, feeling his self control slip. When she pulled off him, his cock was colored an angry red, a pearl of precome beading from the tip.
Dimitri grabbed a pillow, adjusting himself, but let out a sudden gasp as Byleth slammed her hips down again, him now facing her ass as she continued riding him roughly. This time, she gave him no room to breathe, thrusting down at a punishing pace as the vestiges of his control slipped away from him.
“I said I’d fuck you dry,” Byleth growled, looking back at the man beneath her. Her tail, which had been teasing his nipples with its tip, jutted forward, wrapping itself around his neck, forcing the tip into his mouth. Dimitri’s face squinched, his balls tightened, his fingers fisted in the bedsheets, “Who’s the little slut now ?”
Dimitri came with a loud grunt, streaks of white erupting from his cock to paint Byleth’s insides white. He barely registered Byleth coming again with a signature wing flare and fire eruption, the burst of warmth inside her just too much. Dimitri’s senses were too far flooded with heat and wetness and friction; the world was out of focus, his world, Byleth, the only possible thing he could perceive. Cum leaked shamelessly out of Byleth, and she gathered some up with her tail, rubbing it into her skin, eliciting a sigh from the heat-drunk demidragon.
The sight of Byleth indulging in his spend lit a fire inside Dimitri, one more intense than the heat of Ailell. With a possessive growl, Dimitri pulled Byleth off his cock, flipped her over, and began rutting into her incessantly, head of his cock striking her womb with every powerful thrust. Byleth screamed, wings flaring to lay flat against the bed, tail curling around Dimitri’s torso to bring him even closer, nails scratching angry lines of red down his back.
Dimitri leaned down, capturing Byleth’s lips in a passionate kiss, tongues battling for dominance as he spilled himself deep, deep within her again, purple columns of fire illuminating the bed where the couple lay. Separating, a thin line of spit connected their mouths, both of them heaving and panting from the exertion.
“Fuck, Byleth, I... Fuck,” Dimitri heaved, coherency abandoned for the sake of pure lust. Byleth only mewled, replacing Dimitri’s cock with her fingers, begging to be filled again with soft pants and sighs.
Dimitri’s cock stirred with interest yet again, Byleth squirming on the bed as she pumped three fingers inside herself in a feeble attempt to satiate her burning need. “If you’re begging to be filled that much, take it. I’m going to breed you like the beast you are,” Dimitri snarled.
Byleth keened as Dimitri flipped her over, taking her from behind, slamming her face into the pillow. Seeing her horns, an idea popped into Dimitri’s head, and he smirked as he grabbed them to gain more leverage, thrusting into her at a breakneck speed.
Byleth’s tail thrashed wildly, until it stilled, an idea forming in Byleth’s lust-addled mind as well. Wetting itself in a mixture of her slick and Dimitri’s spend, Byleth coiled her tail around Dimitri’s midsection, finding his winking hole with the tip of her tail and swirling the rim with their wetness.
Then she thrust in.
Dimitri moaned, losing his rhythm, falling over the edge immediately as Byleth’s tail struck his prostate. It wriggled within him, claiming every inch of him as hers, wringing another orgasm out of the blonde man with a sputter and an overstimulated cry.
“Mate,” Byleth moaned, removing her tail from his ass and tackling Dimitri onto the bed. Her teeth sunk into the soft flesh of his neck, drawing rose-red blood that she lapped up eagerly.
Dimitri, growling, flipped her back over, laying atop her. Byleth growled, fighting back, flipping him, continuing the back-and-forth battle for dominance. Eventually, the two of them ended up in a seated position. As Byleth moved to take his cock within her again, he noticed her more draconic features were fading - what he took to mean her heat had almost been sufficiently fucked out of her.
“Bite,” Byleth commanded, presenting her neck to him. She bit his neck again as well, drinking more of his blood, shivering as she did. Inside her, Dimitri could feel her walls clench around him, milking him for all he was.
Drunk on pleasure, Dimitri inspected the milky skin of Byleth’s neck, almost salivating at the sight. Baring his teeth, Dimitri bit down, the taste of iron and Byleth consuming him.
_
“I have to hope she doesn’t mark him,” Seteth muttered, pacing back and forth in his office. “If she did, results could be disastrous.”
“Wait, mark? You never mentioned anything like that,” Sylvain said.
“Because the youngest living Nabatean at the moment is Flayn. Or, at least, she was. I had completely forgotten she didn’t know the risks.”
“Wait, so, does Flayn get this heat thing…?” Sylvain raised an eyebrow.
“It’s dealt with. Try something and I’ll show no mercy, Gautier.”
“Jeez, it was a joke,” Sylvain raised his hands up defensively.
“So, what does this ‘mark’ entail?” Felix piped up.
“Female Nabateans have a biological urge to mark, and only females can do it. My late wife wasn’t Nabatean, so she never marked me, which explains why I’m here today. Nabateans who mark a mate essentially bind themselves to their chosen person. From then on, only their chosen mate can satisfy their Dioghras cycle. But, there’s a deadly catch. Mates are marked in both life and in death. If Byleth has marked Dimitri…”
_
Dimitri moaned, Byleth’s taste on his tongue, Byleth’s scent in his nostrils, Byleth’s wet walls convulsing on his cock, Byleth, Byleth, Byleth.
Byleth canted down harder, Dimitri’s blood smeared across her face, fangs stained red.
“...if one were to die, they would both succumb,” Seteth finished.
Byleth moaned shamelessly, head thrown back, wings expanding. Dimitri came with a shout, but kept thrusting, would never stop rutting into Byleth.
“If she’s had him drink her blood,” Seteth started.
They thrust in unison together, kissing like their lives depended on it.
“And if she’s consumed his blood…”
Byleth cried out. Dimitri grunted.
“Then, the mark is complete.”
Bright, unflinching light peeked through the curtains of the Archbishop chamber, Byleth rousing with a groan. Rubbing her eyes, she suddenly felt...wet. Looking down, an obscene amount of cum was pooling from her pussy. Her ass too, she realized. When did he…?
“Professor! Are you decent?” Mercedes called from behind the door.
“Uh,” Byleth threw the covers back over herself, “now I am!”
Mercedes walked in the room, a steaming cup of liquid in her hands. Sitting down on the bed, she offered the beverage to Byleth, who took it gratefully.
“It’s a contraceptive tea. Can’t quite have you getting pregnant,” Mercedes laughed.
“Thank you Mercedes. By the way...where’s Dimitri?” Byleth was saddened to not see him when she awoke.
“Oh! He’s in the cathedral, as usual. Same spot.”
“Thank you, Mercedes. Now, if you don’t mind, I need a bath.”
“Of course, Professor! Have a nice bath. Feel free to call me if you need anything,” Mercedes said, walking out the door.
Bathed, contraceptive tea drunk, and not dripping seminal fluid, Byleth headed to the cathedral, and was met with the familiar sight of Dimitri’s back, a clean line of scratches visible under his cloak. In fact, all types of marks could be seen on every inch of Dimitri’s skin, confirming to Byleth that yes, last night did indeed happen.
She approached the man. “Dimitri, are we-”
“Go away.”