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Kiyoomi didn’t peg himself as the jealous type. It wasn’t in his nature, yet the resent and panic stirring deep in his belly didn’t bode well the longer he stood watching Atsumu converse across the court with another Omega.
They’d just lost their game, plus it was already so late, so it was no surprise to anyone that Kiyoomi felt like shit. He didn’t blame himself in particular for losing, but his competitive nature wouldn’t allow him to take a loss gracefully in the first place. Normally, he’d be speeding off to the locker room by now to scrub off the negative thoughts in the shower, but tonight he wanted to wait for Atsumu first who was supposed to be doing an interview.
But instead, his boyfriend was leaning against the wall of the gym some ten feet away with a towel slung around his neck, gleaming with sweat and towering over a pretty Omega reporter girl who kept giggling all over him without a care in the world.
Kiyoomi couldn’t decide if he should ring her or Atsumu’s neck first.
She wasn’t even doing her job, only bothering Atsumu for her own amusement apparently, and Atsumu must’ve been completely fine with it if the length of their long conversation meant anything at all.
Bitterness crawled up Kiyoomi’s throat as vile thoughts crept into his mind, because it actually did make sense in a way.
She was beautiful, just like Atsumu, so Kiyoomi couldn’t really blame his Alpha for forgetting about him the moment he saw her. The public didn’t know about their relationship, so there wouldn’t be any backlash on Atsumu other than from Kiyoomi himself.
A sharp, raucous laugh reverberated through Kiyoomi’s ears and he winced. She must’ve said something funny for Atsumu to be laughing that hard. He didn’t laugh that much with Kiyoomi around.
And it’s not like this came out of nowhere–it had been building up for a few weeks now. He knew his boyfriend was popular, had known it before they started dating, even. But that didn’t mean he was prepared to face the reality of it—of this—Atsumu deciding to flirt like he wasn’t in a relationship anymore.
And maybe it hurt because she was everything Kiyoomi wasn’t–pin straight blonde hair, curvy, barely reaching Atsumu’s chest in height. A better Omega by all the right standards.
Kiyoomi’s back went rigid, body freezing as a terrifying thought crashed over him—their relationship was so fresh. Did Atsumu regret courting him by now?
Was three months all it took for him to get bored of Kiyoomi?
Then the girl giggled again, and dread pooled in Kiyoomi’s stomach as he watched her lean forward to casually touch Atsumu’s bicep, whispering something into his ear. Atsumu laughed animatedly, bending over to clutch his stomach.
Anger bubbled inside of Kiyoomi, blistering red and angry; he couldn’t just stand and watch this revolting scene anymore. It had gone on for too long, and it wasn’t like him to stay so complacent. With a new resolve, Kiyoomi struck.
“Atsumu,” Kiyoomi snapped forward, “Foster wants to talk to us in the team room.” He lied, shooting a withering glare at the girl before Atsumu could see. It was in bad taste, but he couldn’t help it.
Atsumu perked up at the sound of his voice, humming in acknowledgment towards Kiyoomi. Kiyoomi was glad that he had already put on his mask, because otherwise he wouldn’t have been able to hide the wide smirk that had spread across his face.
But he should’ve known things weren’t going to go his way tonight.
Atsumu turned back around to say his goodbyes to the girl at the same time that she lurched forward to desperately sink her nails–rather claws–into Atsumu’s forearm and scrawl her phone number across his skin in permanent marker.
Kiyoomi’s smirk fell, and he blanched, paralyzed in place while Atsumu yanked his arm back like he’d been burned.
Kiyoomi couldn’t control himself; at once, his scent soured, the severity of it catching the attention of several people nearby who were all now looking for the Omega in distress with a hushed murmur.
Atsumu, who had looked so casually content mere seconds ago, was now looking more like a deer caught in headlights as he frantically looked between Kiyoomi and the girl.
“Kiyoomi, it’s not- that isn’t- I didn’t ask for it!” Atsumu explained, stumbling over his words as he madly wiped at his arm with the palm of his hand, the fresh, dark ink smearing and only making it look worse.
Nothing Atsumu said mattered right now in Kiyoomi’s addled brain. Kiyoomi opened his mouth to say something, but nothing would come out. He couldn’t form a single coherent sentence. No, the only thing clear in his mind at the moment was the fact that his heart was pounding with a twisted cruel jealousy, and that Atsumu just brazenly flirted with another Omega in front of his eyes, like he was some pushover.
With a head full of envy, resentment, and misery, Kiyoomi figured it would be better to leave without another word instead.
So, he bolted.
Kiyoomi rushed out of the arena and into the athletics hallway, refusing to make eye contact with anyone even though he heard his name being called several times. His breath grew short, Kiyoomi’s Omega growing more alarmed by the second, and he hated that he had no real privacy readily available to stop and calm down. He had to fight against his nature, refusing to break down in public.
He just needed to get to the locker room, then he’d be fine.
Heavy footsteps sounded behind him, and Atsumu quickly caught up to Kiyoomi, out of breath with a nervous laugh and an explanation ready in hand.
“Um, baby-“ He tried to start, but Kiyoomi growled on pure instinct, small Omegan fangs peeking out as a warning for Atsumu to back off.
Atsumu balked, shutting up as he fell into a silent step behind Kiyoomi with obedience, but that wasn’t good enough. He needed to be alone. He pushed forward, rounding the next corner with a speed that was unlike him.
When they entered the team room, Atsumu glanced around before hesitantly asking, “I thought coach wanted to talk?”
Kiyoomi shot a glare before hissing, “I lied,” and bumped into Atsumu’s shoulder as he walked past him toward the Omega locker room. He would be lying again if he said he wasn’t a little smug to watch Atsumu stumble backwards and into the wall.
But the pleasure was short lived, because once he was alone with his thoughts under the running water of the shower, insecurity swept over him in a suffocating wave and breathing became even more difficult.
He allowed himself to break down. In truth, he’d never gotten quite used to being an Omega who didn’t look like a typical Omega. All his life he’d been acutely aware of how different he was. The little comments from his mother and schoolmates made sure he never forgot it.
He was much too tall and far too muscular for an Omega. His mother had taken him to the doctor several times because she felt like something wasn’t right, but that didn’t change the fact that he still got heats, or that he had a womb, or that he smelt like any other regular Omega. But she couldn’t see that.
And maybe Atsumu was realizing it too, just like her.
Now, he was scared. He was scared that Atsumu would wake up and realize he wasn’t good enough. That he’d made a mistake choosing Kiyoomi.
When Kiyoomi blinked, the sight of Atsumu laughing with that other small, tiny Omega was burnt into the back of his eyelids, and he spiraled underneath the running water.
It was funny–he should’ve known that it eventually boiled down to the fact that Atsumu was a stupid knot head, just like every other Alpha that Kiyoomi had ever encountered in his life.
That must be the only explanation. Atsumu probably just wanted someone to sink his knot into, and now that he’d gotten it, he was bored.
Kiyoomi felt sick, tears threatening to spring to his eyes as he fiercely scrubbed at his face to stop them. It took several minutes for him to ebb them, and he spent an unusual amount of time slowly washing his hair and body, if only to wash the thoughts away too. It was the most emotionally taxing shower Kiyoomi had ever taken, and once he was finally out, he was left nauseous and borderline ill.
The only other Omega on the team was Hinata, who gave Kiyoomi a wide berth as his sour scent permeated the locker room worse than before, exacerbated by the steam of his lengthy shower.
He didn’t blame Hinata for avoiding him, just like he couldn’t blame Atsumu. Maybe if he were a shorter Omega like Hinata, Atsumu might not regret their relationship in the first place—might not be so embarrassed to be seen together.
Kiyoomi toweled off and dried his hair at a snail’s pace. He didn’t want to face Atsumu, not when he hadn’t calmed down even a tiny bit. For once, the Omega locker room felt like a sanctuary rather than the usual scalding-hot iron brand announcing what he was to the world.
As he gathered his things to leave, he half-hoped that Atsumu gave up on waiting and went home without him, but when he stepped out of the locker room, he found Atsumu meekly waiting on the couch after his own shower. He looked small.
Kiyoomi faltered at the sight. He was certain that Atsumu wouldn’t walk him home today, yet here he was. Had he been too hasty with his thoughts?
Atsumu waited for him after his rightful outburst, that surely must mean something.
“Ya ready?” Atsumu stood up, offering his hand out courteously for Kiyoomi to take.
It was meant to be a kind gesture, but Kiyoomi could still see that Omega girl’s dirty hands feeling him up, even if he did just take a shower. Kiyoomi turned his nose up, and in doing so, he almost missed the ink of a phone number that was still present on Atsumu’s arm.
A white-hot lick of fire raced down his spine so fast that Kiyoomi flinched, and a quiet laugh escaped his lips.
Kiyoomi wasn’t stupid, nor some helpless Omega. Atsumu must think him a fool if he would go anywhere with him right now.
“Oh, fuck off, Miya. You didn’t scrub it off? What, you want to call her or something?” Kiyoomi asked, vile accusations bubbling from his lips without second thought. He kept going, unable to stop. “Actually, why don’t you just call her right now if you want to keep it so bad? You can walk home with her instead!” He laughed again, though nothing about the situation was funny.
“The fuck are you talkin’ about!?” Atsumu’s voice rose, face growing red in anger. Kiyoomi scoffed, entirely unamused now.
“Whatever. I don’t care. Just do what you want, like you always do anyway. I’m going home,” Kiyoomi spat before turning on his heels and walking out the door, not allowing Atsumu to have the chance to speak. It didn’t matter, he didn’t want to hear it anyways.
Deep down, Kiyoomi knew that he was being irrational. He didn’t actually believe that Atsumu would go and call the Omega girl, but he was still relieved when he heard Atsumu follow him out the door and out the building.
The night air was chilly, and the walk to Kiyoomi’s home was in a tense silence, so Kiyoomi wasn’t sure what he should expect when they made it up the steps to his apartment and stopped at his door.
Kiyoomi was trembling. He knew it was illogical to still be this angry, but they’d just lost their game, and Kiyoomi was nearing his heat, and that Omega girl had been too touchy. He didn’t have to like any of it. Atsumu shoved his hands into his pockets angrily.
“Look, I’m not lettin’ ya run away. I dunno what’s goin’ on in that head of yours right now, but we need to talk. I’m coming inside,” Atsumu grumbled. Kiyoomi didn’t even get the chance to say no, because Atsumu was pushing past and taking off his shoes in the genkan just like he had so many times before.
As soon as they were both inside, Atsumu immediately retreated into the guest bathroom where Kiyoomi heard the shower water turn on, and can only assume that Atsumu was working to scrub off the rest of the ink from his skin unless he had decided to turn over a new leaf and become a clean freak, too.
Kiyoomi scoffed angrily in his direction. He had some nerve, coming in here like he owned the place. He didn’t have to listen to him. He was going to bed, and that was that.
But Kiyoomi’s head barely hit the pillow before Atsumu was slamming the bathroom door open. Kiyoomi jolted up in fear, the sudden, thick scent of upset Alpha pheromones rolling into the air as he swung his legs over the side of the bed.
“Do you mind?” Kiyoomi deadpanned, and Atsumu growled, stepping toward the bed with visible frustration.
“Nope, it’s my turn to talk now. You don’t get to just go to sleep now, not after tonight.” His voice was filled with so much vitriol that Kiyoomi’s inner Omega almost wanted to cower, but he remained steadfast as he tilted his chin up to Atsumu. “Fine. Go on then.”
Atsumu rolled his eyes. “Kiyoomi, please keep in mind that this is permanent marker. I tried gettin’ it off the first time, and if ya had let me speak back at the gym, ya would’ve known that. But ya ran yer mouth instead and then ran away.”
“Well, you let her write the whole number. You could’ve stopped her before she finished,” Kiyoomi pointed out.
“Oh, come on. That’s hardly fair, and you know it. It happened too fast for me to process. I froze up,” Atsumu defended himself, and Kiyoomi guessed he might’ve done the same thing if he were in his shoes.
“Well, not to mention I watched you flirt with her for almost twenty minutes when you were supposed to be doing an interview.” Kiyoomi raised his brows expectantly.
“I wasn’t flirtin’ with anyone! And she was interviewing me the whole time! God, you can be so stupid sometimes for someone who’s normally always so smart.” Atsumu stressed, and Kiyoomi stilled at the backhanded compliment. Atsumu sighed, shaking his head.
“Sorry, I didn’t mean all that. But I’m serious. I was just playin’ it up for the recording. I didn’t realize she was tryin’ to flirt with me. I’m sorry for not walking away sooner. But yer the only one for me, and I need ya to realize that.” Atsumu paused as his face morphed into a more relaxed expression, before kneeling on the floor in front of Kiyoomi to interlock fingers. Kiyoomi squeezed them tightly together once they were connected, hesitating before speaking his next words.
“I don’t want you to ever talk to her again. If you’re serious about us, I mean,” Kiyoomi quietly demanded. Atsumu paused, swallowing before nodding.
“Okay, I can make sure that happens. I’ll never even look in her direction again. I’m dead serious about us, baby,” Atsumu reassured him.
Kiyoomi glanced at Atsumu’s arm. At least the marker was a bit more smudged off now, but Kiyoomi could still see faded black ink etched into the grooves of his skin that realistically wouldn’t go away for a few more days. Still, his words didn’t sit well with Kiyoomi, so he mustered up the courage to finally ask.
“Then. . . why is our relationship a secret?” Kiyoomi’s voice came out in a whisper, and a rush of fear suddenly wrapped him up so tightly that his heart clenched–his Omega was so confused and hurt. He could feel his face scrunch up in pain, and it was times like this that he hated being an Omega, having no choice but to give into his own biology.
Atsumu’s face fell, and he brought his other hand up to wrap over their interlocked fingers.
“I thought that’s what you wanted?” Atsumu asked, brows pinched together.
“Me? I never said anything about that,” Kiyoomi said, leaning back in confusion.
“Exactly,” Atsumu stressed, “Ya never said anything. Ya don’t ever post pictures ya take of us. Ya don’t talk about us to anyone. Not a single person in yer life knows about us! Not even yer cousin! How else am I supposed to interpret that?” Atsumu stressed, squeezing Kiyoomi’s hand impossibly tighter.
“That’s not fair, Atsumu,” Kiyoomi shook his head in protest, but slowly he was realizing that maybe he was the one who forced their relationship into that direction. Still, he had never asked Atsumu to keep quiet.
“Is it? Baby, yer the most private person I’ve ever met. I mean I guess I should’ve asked, but I thought this is what ya wanted. I was tryin’ to be respectful.”
Kiyoomi’s throat was closing up and those tears he’d managed to hold back earlier were welling up once again. God, when had he turned into such a crybaby? He didn’t think he’d ever cried this much in his life, not even when he broke his arm as a kid.
“You’re right.” Kiyoomi felt a tear roll down his cheek, and Atsumu was quick to wipe it away. “You were being respectful, and I never even brought it up. I should have asked too, but I don’t want our relationship to be private. I thought. . . You wanted to hide me. That I was embarrassing to you,” Kiyoomi sniffed, and even though every word was a hit to his ego, it had to be said.
“What? No! God, no. Yer—fuck, yer not someone who should ever be hidden away. Ever,” Atsumu started, fumbling his way through reassuring Kiyoomi, who’s scent was still so stiflingly sour that he felt the need to go open the window and air out the room.
Atsumu must’ve smelled it, must know exactly what Kiyoomi needed deep down, because he took one final deep breath before looking Kiyoomi in the eye and giving him a determined look that stirred something in his chest.
“Ya know, I really wanted to save this for a fancy date or somethin’, but I think now’s the best time,” Atsumu started, still kneeling on the ground below Kiyoomi. “So, Sakusa Kiyoomi, my darlin’ Omega, light of my life, my sweetheart.”
Kiyoomi was secretly pleased at the crooning, but feigned annoyance. “Just get on with it. Don’t beat around the bush,” He urged, and Atsumu chuckled, reaching forward to brush a stray curl back into place.
“First of all, let’s go public. We’ll deal with whatever happens together. Not that anyone should care, but we’ll probably get some shit about dating as teammates—whatever. Let them talk.”
Kiyoomi nodded slowly. “Okay. I’d like that.”
“Good,” Atsumu paused.
And then, “Secondly, I love you.”
Oh.
Oh.
Kiyoomi’s lips pursed, and he stared down entirely dumbfounded at Atsumu for a brief moment before he could respond. That was the last thing that he expected out of Atsumu’s mouth tonight. So instead of saying the right thing, the romantic thing, instead Kiyoomi responded with, “You love me?”
Atsumu stood suddenly, and kissed him hard, before leaning back to thread his fingers into the shorter hairs at the nape of Kiyoomi’s neck.
“Kiyoomi, I love ya more than any words can describe. I love ya so much, I’d mate ya right now if you’d let me,” Atsumu confessed with a blush, and Kiyoomi’s stomach did somersaults into the next room as his core was jarred at its very being.
“You can’t just say things like that.” Kiyoomi said breathily, suddenly feeling the urge to fan himself.
“But I mean it. Every last word. I swear it.” Atsumu sat next to Kiyoomi, leaning in close to give a peck to his jaw.
“That’s ridiculous. How can you be certain about something as important as that when we’ve only been together for three months? You’ve never even seen me in heat. Besides, I’m… I’m nobody’s perfect Omega. You’d be stupid to mate someone like me,” Kiyoomi blurted, embarrassed to even admit it aloud.
Atsumu’s brows shot up as his hand fell. “Excuse me?” His voice lifted at the end, almost as if he were offended. Kiyoomi swallowed hard, glancing down at his own large hands.
“I mean, come on. Look at me.”
Atsumu gave Kiyoomi a once-over.
“All I see is my sexy, sexy Omega. What am I missin’?” Atsumu crossed his arms with a frown, almost as if he dared Kiyoomi to challenge him.
Kiyoomi bit the inside of his cheek, still unconvinced.
“I’m too tall. And far too muscular. You’re not naive enough to not recognize that this isn’t typical for most Omegas.” Kiyoomi fiddled with his thumbs, refusing to make eye contact, but Atsumu wouldn’t let him shy away. He grabbed Kiyoomi’s hands again, rubbing small circles against his fingers.
“Kiyoomi, isn’t that what makes ya special? Isn’t that what allows ya to stand on the same court as me? Don’t ever think yerself as less of an Omega because of that. Yer special and perfect,” Atsumu stressed, hands making their way up to hold Kiyoomi’s waist.
Atsumu’s eyes were so doting, and the look of deep affection was undeniable, even to Kiyoomi. He was surprised to find some consolation in it. He didn’t feel as bad anymore, but the lingering insecurities would probably always find him no matter what anyone told him.
But Atsumu?
He’d always be there. Kiyoomi knew that, deep down. Atsumu had never not been by his side. Always returned his calls, even in the middle of the night. Had never not missed a date, or a meeting, or a birthday. He’d been such a gentleman, going to great lengths at making sure Kiyoomi felt comfortable at all times in his own skin. Knew his boundaries, his likes, his dislikes, and more.
And they’d only been dating for three months.
But in truth, it was longer than that. It was years. Years of training camps, and friendly conversation, and bickering that Kiyoomi never truly minded. They’d known each other for what, five years now? Atsumu wasn’t going to change now that they were officially dating.
“Omi, are ya okay? Yer spacing out,” Atsumu asked, snapping Kiyoomi out of his head.
Kiyoomi looked hard at Atsumu’s face.
“Let’s do it,” Kiyoomi whispered, gaze still fixed forward.
“Sorry?” Atsumu asked, a little lost and a lot concerned. Kiyoomi cleared his throat, building the confidence he needed as he squared up to face his boyfriend.
“Let’s do it. Mate, I mean,” He clarified, and Atsumu choked on his own spit, sending himself into a lengthy coughing fit. Kiyoomi patted him on the back stoically.
“Huh? Mate!?” Atsumu asked, eyes bulging out of their sockets. Kiyoomi half-wanted to shrink back defensively again, but he refused to be afraid anymore. He crossed his arms expectantly.
“You said you’d mate me right now if I let you. So, I’m letting you. Were you not being serious?” Kiyoomi asked, tilting his head to the side.
Atsumu stammered, hands motioning uselessly in the air as he tried to make sense of his words.
“Yeah! Yes, of course I was bein’ serious! I want to, I just didn’t think y’were- I mean shit, okay!” Atsumu stuttered out, “I really want to be yer mate,” He added on with as much sincerity as he could muster.
Kiyoomi breathed another quiet sigh of relief, and finally allowed his shoulders to relax for the first time all evening.
“Okay then. Let’s do it.”
-
The air was charged with something nerve wracking. In only thirty minutes, the mood shifted from a tense fight and into something a bit more… rousing. Atsumu had insisted that they at least try to spruce up the room a bit, to make it a little bit more romantic. He let Kiyoomi fix up his nest the way he wanted it while Atsumu tried setting the mood by lighting Kiyoomi’s almost already melted Summer Nights special edition candle even though it was the middle of winter.
Even after all of his fussing with his nest, when it was time to face each other on the bed, Kiyoomi was nervous.
Not necessarily because he was about to be permanently bonded with Atsumu forever, but more so that it was actually happening. Would it be painful? Kiyoomi had no clue, because he tended to avoid learning about that sort of thing, and it’s not like his mother ever thought to discuss it with him either.
Truthfully, Kiyoomi never planned on mating with anyone. He never thought he’d even have to face this in his life, never thought he’d find an Alpha good enough for him, but then here came along Atsumu anyway.
“Hey, quit overthinking. If yer not sure about doing this, it’s okay if ya wanna wait. We can wait,” Atsumu soothed, settling in close to Kiyoomi who was already shaking his head. He had already made his decision, and knew that there would never be anyone else in the world that he’d want besides Atsumu.
“No, I want to. I want you. I’m just a little nervous, that’s all,” Kiyoomi confided. Atsumu pumped some calming pheromones as he rubbed Kiyoomi’s shoulder before gently pulling him forward to get closer.
“Hey. C’mere,” Atsumu murmured, cupping Kiyoomi’s cheek and pulling him into a deep kiss so that they were sealed together. Atsumu’s lips were a little chapped, but he didn’t find that he minded at all. In fact, the contact was electrifying, and seemed so much more different already than the last time they’d had sex. It was almost like his Omega inside of him knew.
Atsumu shifted, and then a hand glided down Kiyoomi’s chest, wrapping itself up in the cotton fabric of his shirt at the hem. Obediently, Kiyoomi raised his arms up so Atsumu could help him out of it.
“Gorgeous Omega,” Atsumu murmured seemingly to himself before leaning forward to leave chaste kisses across Kiyoomi’s chest and nipples, down to his navel where he paused to inhale deeply.
“Yer scent drives me crazy,” Atsumu confessed, fingers tightening around Kiyoomi’s sides as he licked a stripe up his stomach in such a possessive manner that Kiyoomi slicked up. Atsumu stilled, eyes snapping up to meet Kiyoomi’s.
The eye contact sent a shuddering chill down his spine, instincts begging him to open his mouth and plead for a knot. He whimpered as he felt his mind beginning to unravel and give in to his biology.
“Atsumu, please—need your knot. Hurry up,” Kiyoomi demanded breathily. Atsumu’s pupils widened.
His Alpha couldn’t wait any longer after that, and scrambled to yank Kiyoomi’s pants off in a rush, enticed by the scent of growing slick. “I’ll make ya feel so good, Omega. Yer never gonna forget it after tonight. I promise.”
Kiyoomi couldn’t argue with that.
Atsumu took his sweet time settling Kiyoomi up against the pillows and spreading his legs apart. He was left only in his panties, and the large damp spot on the fabric was embarrassing to no end, but even furthermore when Atsumu leaned in close to study it.
“Atsumu, quit stalling,” Kiyoomi whined, shying away from Atsumu’s touch against his knee to encourage him to touch elsewhere.
“Patience,” Atsumu crooned, and Kiyoomi snorted, but he was flushing as he muttered, “Says you.”
But Atsumu didn’t give into Kiyoomi’s demands. Instead, he took his time with feather light touches, fingers dancing along the insides of Kiyoomi’s calves and thighs, ghosting over and in between his legs from where he wanted to be touched the most until Kiyoomi was bucking into the air looking for contact, anything to appease the growing heat inside him.
Atsumu smiled up at Kiyoomi before leaving a kiss on the mole of his hip bone. Kiyoomi’s breath hitched at the tenderness of the action, before he was cut off by Atsumu’s fingers pushing his panties to the side.
Immediately, his finger made contact with Kiyoomi’s clit, gently rubbing circles into it while his other hand traced downwards through slick to find his entrance, but it wasn’t fast enough.
“Please,” Kiyoomi begged.
Atsumu’s tongue darted out to wet his lips, and his fingers dipped inside, sliding into place against Kiyoomi’s walls as he curled them upwards. “Oh!” Kiyoomi nearly lurched forward at the motion, involuntary clenching around Atsumu’s fingers.
“Damn,” Atsumu whispered, swallowing hard as he greedily took in the sight of Kiyoomi’s hole conforming around him. He couldn’t seem to decide where he wanted to look, gaze rapidly darting between Kiyoomi’s face and pussy, hyper-focused on every little action and sound made.
“Yer feelin’… Fuck, I don’t know how to put this, but like, spongier than usual? Is that a weird way to say that? Are you about to start yer heat?” Atsumu asked, curling his fingers against Kiyoomi’s walls in just the way he liked and yes, he definitely was if the slick drenching Atsumu’s fingers were anything to go by.
“Ah—Yes, soon. Next week, probably,” Kiyoomi panted, eyes squeezing shut and back arching as Atsumu found his sweet spot again.
Atsumu was quiet in response, and when Kiyoomi looked up curiously to see why, he was surprised to find a deep, predatory hunger in his eyes, and a sudden wave of thick Alpha pheromones washed over the room, invading all of Kiyoomi’s senses at once.
“Oh,” Kiyoomi whimpered, turning to the side to bare his neck. Atsumu’s fangs were peeking out and he chuckled.
“Ya can’t seem to remember who ya belong to. How about I help ya remember, Omega?” Atsumu breathed, alluding to earlier tonight as he nosed along Kiyoomi’s neck, and a new wave of slick wafted through the air to mingle together with Atsumu’s scent.
In the next moment, Atsumu’s pants were off, thick cock springing free from his underwear until it was slapping heavily against his stomach. Kiyoomi’s eyes went wide when he noticed a swell already beginning to form at the base–Atsumu was ready.
He pressed forward so that his cockhead brushed against Kiyoomi’s folds, licking at the side of his neck before growling, “Yer sleepin’ with my knot in ya tonight,” He rocked forward, eliciting a whine from Kiyoomi. “Wanna mate ya, baby,” Atsumu grunted, hands gripping and kneading at Kiyoomi’s ass.
The instinct to present hit him like a weight, and with a power he didn’t know he possessed, Kiyoomi wriggled out from Atsumu’s grip to turn himself over, pushing his face into the sheets and his ass into the air.
Atsumu groaned from behind him at the sight. “God, yer so perfect, Omega. Let me take care of ya.”
Kiyoomi cried out as Atsumu finally buried himself inside. It was everything he needed to forget about what had happened today. There were no more thoughts of jealousy, or rage, or depression; only Atsumu. He loved him. They were going to bond, right here, right now.
Atsumu rocked into Kiyoomi carefully at first, setting his pace steadily before wrapping a hand around and in between Kiyoomi’s legs to circle at his clit once again.
“God, yer soppin’ wet. Feel good, baby?” Atsumu asked as his pace grew faster. Kiyoomi’s eyes were screwed shut again because yes, yes, it feels amazing. His legs were already starting to tremble, and he wasn’t sure how long he’d be able to keep himself propped up like this.
“Yes. I love it. I love you.” Kiyoomi gasped at a particularly deep thrust. He clenched down involuntarily in response, and Atsumu moaned softly into his ear. Kiyoomi finally said it back, and he meant it in its entirety.
“I love you. I love you,” Atsumu repeated twice as he continued fucking into Kiyoomi. He brought his other hand up to Kiyoomi’s nipple before pinching it, and Kiyoomi physically had to pull away from the sharp pleasure.
“D-don’t! I’ll cum too quickly,” He tried, but Atsumu wouldn’t hear of it. He was chasing a high of his own, of getting Kiyoomi off, of making Omega feel good.
“Atsumu!” Kiyoomi bit his lip. The knot in his belly was starting to pull tighter and tighter, and he wasn’t sure if he could hold on much longer as Atsumu’s thrusts and ministrations turned erratic.
But it was the nip at his neck that did Kiyoomi in–Alpha fangs glided right over the spot where he was meant to bite Kiyoomi to bond them together forever–the teasing tipped him over the edge. A zip of electricity shot through him all the way to his toes, walls clenching tightly around Atsumu’s cock as the knot in his belly snapped.
Slick gushed from him, drenching the two of them and the nest below as his hole pulsed in an attempt to milk Atsumu’s cock. He was sobbing, a complete mess as he rocked against Atsumu to ride out his orgasm.
Atsumu cursed above him, face contorted in an intense focus so as not to cum quite yet.
“Turn over,” Atsumu commanded tersely, and Kiyoomi complied as best he could, but he was stiff in the aftermath of his orgasm. Atsumu helped him the rest of the way, settling Kiyoomi onto his back, guiding his legs into the air and folding him in half. Into a mating press.
It hit Kiyoomi–it was time.
There was no going back now. Atsumu wrapped both of his hands around Kiyoomi’s ankles, pressing inside with a grunt, and this time Kiyoomi could feel just how much his knot had swollen. It was definitely going to pop soon.
Atsumu was heaving, sweat beaded along his temples causing his hair to stick to his forehead, and Kiyoomi couldn’t help but admire the sweet, muscular figure looming above him. He was so attractive, the perfect Alpha to bear children for. Kiyoomi gasped at the thought.
The next thrust was so deep that he saw stars.
“Atsumu!” Kiyoomi cried out, and Atsumu bent down to rest his forehead against Kiyoomi’s own so that they were nearly eye to eye. He was still panting, so Kiyoomi took the opportunity to lean up and meet Atsumu in an open-mouth kiss.
It was messy, tongues meeting in the middle as they licked into each other's mouths, desperate to taste more and more of one another. Kiyoomi hadn’t ever felt so connected to another human being before as Atsumu continued to rock inside of him. He wanted to stay like this forever. Kiyoomi sucked on his tongue, and Atsumu’s hips faltered.
Atsumu leaned back to grunt, “Shit. ‘M about to come.”
Atsumu’s moans were soft and right into the shell of Kiyoomi’s ear as his thrusts began picking up speed. The sound of Atsumu’s heavy balls slapping against Kiyoomi’s ass mixed with slick was the only noise to fill the room until Atsumu opened his mouth with urgency.
“Y’ready? Are ya sure, Kiyoomi?”
In response, Kiyoomi bared his neck.
Atsumu’s thick knot popped and stretched him wide before spilling inside; at the very same time, Atsumu’s fangs sank into the juncture of Kiyoomi’s neck and shoulder, bonding them for life.
A strangled noise escaped his throat, he thinks. It was a feeling unlike any other; something tangible was forming, something that connected him to Atsumu in a way that could never be explained. Like their souls were yoked together to form a bond that would forever be unbreakable.
Atsumu would forever be his.
The kiss that came after was something special. It wasn’t filled with lust like earlier, but something much more tender, and the clarity that hit Kiyoomi would’ve probably knocked him over had he not already been laying down.
He loved being an Omega. Atsumu’s Omega.
This was what it meant to be one.
It didn’t matter what Kiyoomi looked like, or how he acted, or what his mother said. The only thing that mattered was this. Atsumu.
“Kiyoomi,” Atsumu whispered, sitting up as much as he could without pulling at the knot that was sealing them together. He helped Kiyoomi lower his legs down.
“Holy shit,” Kiyoomi breathed in response, and Atsumu laughed breathlessly.
“Yeah. Holy shit,” Atsumu agreed.
“We’re mates.”
“We’re mates,” Atsumu agreed again, wiping the sweat off his brow. “Hey. I’m sorry for bein’ so stupid today. This is the best thing that’s ever happened to me. Yer the best thing. I promise I’ll take care of ya for the rest of our lives.”
Kiyoomi wanted to respond, but he was so damn exhausted that he could only collapse against the pillow. They sat there like that, in a comfortable silence until Atsumu’s knot deflated. Kiyoomi didn’t want to part, but he felt it would be too childish to beg for Atsumu to stay.
“Hang tight, I’m gonna grab us some water.” Atsumu smiled, pushing back the curls at Kiyoomi’s forehead to leave a kiss before standing.
But then, even though he had been satiated, knotted and mated mere minutes ago, his body was growing hotter by the second, and Kiyoomi clutched the sheets fearfully as realization dawned on him.
He was going into heat. A dizzying wave of lust hit him like a truck as he reached for Atsumu’s retreating figure.
“Wait! Alpha!” Kiyoomi pleaded, memory going fuzzy. Why was Alpha leaving his nest so suddenly? Did he do something wrong? He wanted to cry.
Atsumu whirled around at once in confusion, face wrinkled with worry.
“Kiyoomi?” Atsumu stepped forward, taking in Kiyoomi’s scent and desperation as realization dawned over him. His eyes went wide.
“Oh, shit. Already?” Atsumu asked. “Well, I did say y’were sleepin’ with my knot inside of ya tonight. Round two, I guess!”