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"God dammit— fucking— fuck fuck— fucking shit—" Katsuki shouts, stuffing his fists against his face in irritation.
Eijiro whistles appreciatively behind him at the string of curses. "Good news, then?"
"I'm gonna blow your entire head off of your body," Katsuki hisses back, fingers clawing into his skin.
Long story short: They'd just finished fighting off the villain of the day. Katsuki dealt the finishing blow, of course. But the villain had decided that, instead of going down honorably as one does when confronted with higher beings such as himself, they wanted to take one last potshot.
They'd gotten a hit in, grabbing Katsuki by the neck, and set off their quirk.
Whatever the quirk did, though, was slow to activate because Katsuki knocked the bitch out without even using his explosions. Just smacked them across the head with his gauntlet and watched them crumple like melted cheese.
It wasn't until they got back to base that Katsuki started realizing that something was definitely wrong. His gut had a weird feeling in it, kind of fluttering at first before it ached— kind of like hunger but… deeper. And his heart was racing, and…
And he could feel slick gathering between his legs.
Yeah, okay spoiler: Katsuki was an omega. It wasn't something he was ashamed of, but it was… a god damn hassle. With the heats and the constant slick and those shitty nesting instincts.
Plus he's seen how omega heroes have been treated— both by media and by fans— and he knew from an early age that he'd rather hide it than commit actual murder because some horny alpha decided to stick their nose against his scent glands.
So he'd gone through life masked as a beta. Not only that, but a scentless beta. They weren't rare, just peculiar, and he was fine not sticking out in a crowd.
Well.
He was fine being scentless in a crowd.
And he'd been going through life just fine so far! He was diligent with his suppressants, which were extra strength because the only two heats he'd ever had both took him out of commission for two weeks, each. And he had the best scent patches, the kind that soaked in through his skin and weren't noticeable unless you touched.
And Katsuki never let people touch him. Not there, atleast, on the sensitive parts of his neck.
As of age 25, he'd been doing pretty fucking good hiding his omega status.
All of that was going up in shitty flames, though, because a dumbass villain couldn't keep his hands to himself.
"You have the world's shittiest quirk," Katsuki declares, kicking the downed villain in the chest. "And I know a dude whose quirk is growing out his fuckin' toenails."
Mina splutters behind him, trying to muffle her laugh. "How does that even work?"
"They grow two times faster than average, but only if he blinks really fast." Deku helpfully, if not distractedly, replies.
This just makes Mina laugh harder, Eijiro joining her.
The only reason they were even there was because they'd been witnesses to the villain setting off his quirk on Katsuki. They'd just finished filling out the paperwork for the assault when Katsuki got the info back on what the stupid quirk was.
Deku has his hand on his chin as he rereads the files Katsuki dropped on the ground in his outburst.
'Resistance', it was called. Dumbass name. Katsuki didn't care about the minute details about it but basically it made any person's body overlook foreign chemicals in their bloodstream.
Including suppressants.
Katsuki digs his nails into his arms, trying to quell the already rising heat inside of him. His literal heat, which he hadn't experienced in a decade thanks to the wonders of modern medicine that was sitting useless in his arteries. God FUCKING dammit.
The only reason he isn't setting everyone off into early ruts and heats is because, thank fuck, his scent patches were external. He didn't give a shit about the science of it, but it was a respite he was grateful for.
"It has potential to be a good quirk," Deku pipes up, after reading the paper for a fifth time. He flips it down, patting his hand atop the clipboard before he hands it off to an intern.
"The toenail guy?" Mina turns up her nose. "I guess he could slice someone's heels off or something, but he'd have to wear open shoes all the time."
Katsuki rakes his hand down his face. He loved his friends (don't tell them he said that) but sometimes he wanted to dip them in molten mercury.
"This asshole." Katsuki says, kicking at the villain again. They're trussed up in quirk-suppressing cuffs and they have a muzzle on because the heroes hadn't known if it was a voice-activatable quirk or not.
Deku nods, hauling the villain up onto his shoulder so that Katsuki will stop hitting them. "It could've been good for use in hospitals, if someone has an allergic reaction. Or for recovering addicts, maybe."
"We might be getting off topic," Eijiro says, when Katsuki clenches his jaw so hard that his veins pop out.
Thank god for Eijiro.
"… Besides, the quirk shouldn't really do anything to you, right? Since you're a beta!" Eijiro says it cheerily, and Katsuki blanches.
Fucking Eijiro.
Deku eyes Katsuki as Mina and Eijiro start going off on another tangent. Katsuki glares back, ignoring the way sweat beads at his eyebrow and starts to slowly roll down to his chin.
They have a silent conversation that Katsuki, in all honesty, understands 0% of. Deku's eyebrows go up, and Katsuki furrows his in response. Adds a scowl for good measure. Deku nods, seemingly eased, and Katsuki frowns harder.
The villain coughs. Katsuki, hardly even thinking about it, roundhouse kicks him in the gut. It's only a funny accident that Deku gets hit along with him.
---
Katsuki gets suspended from duty. Partly from unnecessary aggression towards a villain (re: roundhouse kick), and also because the agency knows that Katsuki is fucked to the core from this stupid quirk. They had access to his medical records, after all.
"Take a couple days off," Miruko hums, already signing off on Katsuki's mandatory leave. "Find a nice alpha, ride out your heat— come back fresh."
"I hate the words you're saying to me."
Katsuki snatches up the papers that Miruko holds out and stalks off. Everyone in his path ducks out of the way, used to his explosive moods and attitudes.
The only alphas Katsuki knew were…
Mina and Eijiro, who were already engaged together, so they were out.
Yaoyorozu, who was also already in a relationship (with Chubby Cheeks— Uravity. Omega.)
Tsuyu, who… maybe? But, no. Plus she was in South America until the end of the year.
And IcyHot, who was a hell no.
And…
Deku.
So Katsuki was out of options.
Maybe his fingers would be enough this time. He'd have to make it work.
Katsuki heads straight to the locker rooms with the plan of shoving himself under cold water until the slick freezes up his ass and he can hobble home without worrying about leaking through his pants.
And, of course, he's intercepted as soon as he rounds the corner. Deku, because who the fuck else?
"What."
"Are you sure you're alright?" Deku asks, sheepishly. He follows at Katsuki's heels like a puppy as Katsuki shoves under his arm, ducking into the locker room.
He stands directly behind Katsuki as he shovels through his shit, looking for a spare change of underwear that could be thick enough to hold his…. leaking. Awful, gross. Bad.
"Fuck off," Katsuki says, though it has little bite behind it. He rests his head against the cool metal of the locker and drops his shoulders, head suddenly swimming.
Speaking of swimming: his underwear are soaked. He's surprised he hasn't already gotten outed by how much is coming out of him. Surely someone could smell it.
Did slick have a smell? There was like… the thing with pheromones and scenting, right?
Katsuki frowns as he tries to remember, parsing through whatever meager information stuck in his brain from sex-ed.
So here's something fucking obvious:
When you hide your true secondary gender for your entire life, you can't exactly have sex without the other person freaking out. So Katsuki hadn't really fucked anyone— not even when he did try his heats. He'd stuck with his fingers, which sucked but was better than ignoring the feeling at the time.
Katsuki would be damned if he let some fuckbuddy get too comfy and decide to ruin his life by letting it slip that, hey, Katsuki wants to shove his face against someone's neck and tongue at their glands until his asshole literally spills slick.
They were just instincts and— and—
And… fuck. It was getting hard to think. His gut clenches, clamping down on nothing. Fuck.
Katsuki groans, dropping lower to bury his face into his duffle bag. It smells entirely of him, but muted, and it's… not right? There should be more of everyone— of pack in that. He wanted to be surrounded by pack— or…
A warm hand settles between his shoulder blades, right where his spine rests between his dorsals.
"Kacchan?"
Fuck, he forgot Deku was there. At the nerd's voice, Katsuki squeezes his thighs together sharply and, oh fuck his cock is hard. When did that happen?
He needed his suppressants. Maybe it would take the edge off, just a little. Katsuki felt like he was going fucking crazy.
Instead of answering, he shoves his hands to the very back of his locker and tugs everything out in one swoop. Loose bottles clatter loud on the floor, and some lotions and deodorants pop and spill.
Deku steps back quickly, bending down to catch a bottle of hairspray before it rolls off of the bench that it landed on.
Katsuki shivers, both from the loss of heat from Deku's hand on his back and from the cool metal pressing against his arms as he leans into the locker. His breath comes out louder in the small space, echoing.
Deku says something, hurriedly picking up the mess Katsuki makes… taking care of him… good alpha.
At that thought, Katsuki shoots up so quickly that his head smacks into the roof of the locker. He evacuates it quickly, teetering on his heels, and backs away as Deku stands up straight.
"Kacchan," Deku says firmly. He shoves everything in Katsuki's duffle, kicking it beneath the bench as he steps forward.
He crowds into Katsuki's space, though he doesn't touch again, and Katsuki feels his head go hazy. Katsuki wobbles on his heels, wanting nothing more than to shove his hand between his legs and hump it until he cums, and then shove as many fingers as he can fit up his ass, and then… then presenting so that his alpha c-can…
Katsuki's back hits the wall, and he's so overwhelmed that he clings to it. He can't help it when his fingers crawl across his hips to do just what they wanted, getting far enough that they dip below his belt.
Deku's face goes a pretty red as he watches, hurriedly jerking his gaze away. He catches Katsuki's wrist and squeezes, lifting it away. Katsuki's dick throbs, and his head lolls to one side until he has to force it straight.
"Kacchan, you need help," Deku fusses, worry tinging his words even with how flustered he looks.
His palm comes to rest on Katsuki's shoulder, leading him away from the wall. Katsuki can't help the way he hyperfocuses on the contact again, on the warmth soaking through his uniform and into his skin.
Katsuki didn't need help. He needed an alpha.
"Fuck off," Katsuki whispers, swaying as Deku exerts more pressure. He falls obediently to the bench, staring up as Deku tilts his head with a gentle touch to his chin.
He must see how Katsuki's eyes are blown, because he frowns hard and lowers to his knees, so Katsuki doesn't have to strain his neck.
Katsuki doesn't pay attention to a word that Deku proceeds to say, only preens as Deku tries to urge him calm with a deluge of his scent.
Deku was an alpha. Deku could be his alpha. Yes yes yes, his.
"Alpha," Katsuki breathes, mouth dropping open with a moan as a wave of pleasure washes over him just from acknowledging the idea aloud.
Deku's mouth drops open in shock, blush deepening. Katsuki glares, even as he inwardly flutters and preens at having that effect on him.
Fuck this quirk.
But it felt so fucking good.
Deku's eyes have a funny look in them when Katsuki focuses again. They're dark, eyelids drawn lower than usual. And his lower lip is caught behind his teeth as he continues to rub a gentle circle with his thumb into Katsuki's jaw.
"I'll take care of you."
Deku's voice is oddly deeper, more velvet, and Katsuki melts. He leans into the touch, even as he scowls.
Someone comes into the locker room, door squealing loud to announce them. Deku's hand is slow to move away, and when he stands fully his back is to the newcomer, to Eijiro.
Deku's arms cross tight across his chest, shoulders squaring as he glances over his shoulder, and Katsuki is enraptured with the stern (almost possessive?) look that Deku barely hides.
Katsuki is almost completely blocked from sight like that. The only noticeable part of him are his boots.
"Oh, Deku!" Eijiro's voice is joyful and carefree as ever. "Miruko sent me to kick Ground Zero out and get him home."
"I've got it handled."
Deku isn't angry when he says it, but his voice does rumble with the beginnings of a growl. Katsuki clenches his fist to stop them from moving towards his cock again.
Eijiro hums, leaning over to peek at Katsuki still hidden at Deku's front. His eyes narrow just slightly, until he breathes in deep and scents the air. Then his pupils dilate, just a bit, and he turns an incredulous look to Deku.
Fuck. Katsuki knew they could smell his fucking nasty slick. Fuck fuck fuck.
He jumps up, and shoves his hand at Deku's chest. "I've got it handled. Both of you get back to patrol."
Katsuki digs his heel in the strap of his duffle bag to drag it out. Deku backs off, though he doesn't go far.
Instead, he turns to face Eijiro fully, stance defensive.
"I'll… tell her you got it then, bro." Eijiro holds his hands up, turning back the way he came.
He mumbles something about the villain's quirk being reported wrong, and Katsuki tucks that excuse into the back of his brain. Maybe he could salvage the situation a bit once this was all over.
Deku is still there when Katsuki straightens, bag hooked over one shoulder. He didn't need all the shit that was in it, but he couldn't take another five minutes sorting through and picking out what he didn't need to bring. Not when his knees trembled, longing to drop to the ground and let himself be fucked silly.
The most experience Katsuki had really had with sex was his own hand (and a pillow once, during his very first heat).
He can't imagine how intense the pleasure was going to be, wrapping his hand around his dick and stroking it off. Not when even thinking of doing it was making him go crazy.
Before he can shove past Deku and figure out a way home, Deku grabs the bag and quickly untangles Katsuki from it.
"Asshole, give that back!"
"Just a minute," Deku says, opening his own locker. He digs through the mess (literally a mess. The only things not in one pile were the notebooks stacked in the container on the locker door.) and plucks out a change of clothes. "Here."
They're civvies, a simple pair of sweatpants and a t-shirt that says 'applesauce'.
"I'm not wearing this shit."
Deku sighs, though there's a smile edging on his face.
"It's all I've got. And you're… your scent." Deku waves vaguely through the air, glancing away again as his blush comes back. "It'll help cover it up."
Katsuki isn't sure how simple cotton was going to soak in the pheromones that he'd been lathing the entire locker room in. But before he can argue, he catches a whiff of the clothes as Deku holds them closer.
They smell completely of Deku, down to the very last fiber. Katsuki's whining before he can stop himself, suddenly desperate as he shoves his face into the first thing he grabs, the shirt.
It's good. He feels the edges of euphoria flitter across his brain, just from the scent, and he squeezes his thighs together as his hips arch back.
Deku lets him scent it, circling around the locker room once or twice and doing something stupid with his wrists.
It isn't until Katsuki lifts his head away from the shirt and breathes in fresh air that he realizes that Deku was scenting the room. Heavily at that, coating the growing smell of Katsuki's incoming heat.
"You look stupid," Katsuki hisses, tugging the shirt over his head. If he got naked just to put it on, he'd just re-scent the space.
Plus… he'd probably soak through the pants immediately. He can feel lines of it inching down his legs, soaked through his underwear already. He's lucky his pants are mostly non-porous.
Deku laughs softly, but continues to cover the room in the scent until it's overbearing, even for Katsuki.
"Quit it," he barks. "I don't stink that bad, you ass."
He feels calmer, surrounded by Deku's scent. It makes him irritable as all hell, but atleast he isn't humping the air now.
"You don't," Deku agrees, readily. "You smell really good, Kacchan."
Katsuki inwardly preens again. The higher part of his brain wanted to grab the omega inside of him and slap it across the face to get it to fuck off.
"But you smell like omega, too," Deku continues. "If it just smells like me in here, nobody will know your secret."
What.
Katsuki's heart stutters in his chest before it starts beating harder, louder. Deku knew.
Deku, unknowing of the sudden stupor he'd wracked Katsuki with, continues: "I'll text some of the staff and ask them to cleanse the air. Too much alpha scent might set off some bad instincts and all that."
He prances back to Katsuki, grabbing the bag again and holding his hand out to Katsuki as he rambles on, "Plus they have those scent-suppressing cleaning sprays. I would go get one now, but you seem pretty out of it so I'd better get you home quick."
That last part he mumbles, but Katsuki glares anyway. Before he can argue, Deku hands him a sports-water bottle. "Here."
Katsuki grabs the thing with more force than necessary and sucks it down in less than a second. He didn't realize how thirsty he was until the water hit his tongue, cooling him down.
His shoulders drop as he relaxes, and Deku takes the empty water bottle when Katsuki shoves it back.
"Whatever."
---
Deku drives Katsuki to his apartment, windows rolled all the way down as Katsuki rocks in the passenger seat, fingers fisted in the stretchy material of his sweatpants to keep his fingers off of himself.
It wasn't a far drive, because they both lived incredibly close, but it was long enough that Katsuki quickly devolves to chirping moans every time Deku's scent drifts on this side of aroused.
And he was aroused. Katsuki could see it in the way he clenched his jaw so hard that veins popped up, and how his nose flared the more Katsuki's scent soaked into the car.
Which is why Katsuki is flabbergasted when, after Deku has dragged him up the elevator and past the threshold, laying him across his couch, Deku starts to leave.
"What the fuck, Deku."
Katsuki scrambles off of the couch as Deku starts pulling his shoes back on, body aching in a bad way at the thought of him leaving Katsuki.
Leaving his omega.
"I-I have to go back to work, Kacchan. I'll come check on you later, okay? I'll bring more suppressants, too."
Katsuki had suppressants. Months worth of them in his bathroom and his nightstand drawers. He isn't sure how to express this further than exhaling sharply through his nose like an ox and stalking closer.
Deku backs away, though he ends up trapped by the door. A bead of sweat drips down his brow, highlighting the cut of his jaw as he audibly gulps when Katsuki takes another step forward.
"I know the heat hit fast, but you'll be okay. Just go to your nest and do what you usually do."
Katsuki's eyebrows furrow at the mention of a nest. Oh yeah, that was a thing omegas did, right…
Izuku's expression morphs to match Katsuki's own confused one.
"Did you… take down your nest?"
"Never had one," Katsuki barks, defensive.
"You… Kacchan, that's dangerous."
"So is having explosive sweat," Katsuki snorts, grabbing Deku by his collar. "If you leave I'll… I'll— fucking kill you."
"I can't stay. " Deku is firm as he says it, and Katsuki can feel the claws of something dark and cold start to climb into his gut. The rejection stings in a way he doesn't expect.
"I'm barely controlling myself as it is, Kacchan." Deku enunciates the words by pulling his hands away from Katsuki's hips, where they had unconsciously drifted.
"Then stop controlling yourself." Katsuki steps back, swallowing a lump in his throat.
This could backfire spectacularly but…
Deku was the only alpha that Katsuki could ask for help. Was the only one he wanted to ask for help. Even beyond hiding his secondary gender, beyond hero work… Katsuki trusted Deku more than anything.
"Stay with me, alpha."
Izuku freezes, eyes wide.
Then, Katsuki finds himself shoved against the nearest wall.
Izuku had cleared the room, gathered him up by his hips, and pressed him against the wall furthest from the door. The impact makes Katsuki wheeze, but then he gasps for a whole different reason as Izuku grinds right between Katsuki's legs. Their groins slide together and Katsuki trembles with need.
Izuku's eyes are still dark as he watches Katsuki's every reaction to him doing nothing more than hold him. He presses his thumb to Katsuki's chin, tender, and tilts his head up so that their lips are just a breath away.
"I won't be able to hold back," Izuku reiterates. Katsuki snarls, literally, and grabs onto Izuku's shoulders to jump up and wrap both legs around his waist.
"You're so fucking slow," Katsuki growls. He shoves their faces together, capturing Deku's lips in his.
The kiss is messy and sloppy, and inexperienced on Katsuki's end. He doesn't know what to do beyond keeping them parted and holding his breath.
But Izuku seems to know perfectly what to do.
He eases Katsuki's head back an inch, tilting it. With the new angle, he can ease Katsuki's lower lip between his own and lightly suckle and nibble on it, and trail to the left to pepper more chaste kisses at the curve of his mouth.
Katsuki can't even ease the pressure between his legs by squeezing them closed. All he can do is hold on tight as Izuku traps him against the wall and kisses him silly.
"Fuck."
Izuku is the one who pants out the curse, pulling away too soon. His hand curves around to grip Katsuki's ass, to continue supporting his weight and half to feel the firm muscle beneath.
Suddenly, there are too many layers between them. Katsuki could barely feel Izuku's touch between the sweats atop hero gear atop underwear.
"Shit, hold on."
He smacks his hands on Izuku's shoulders, until the other shifts back and lets him drop.
Katsuki gets tangled in the t-shirt almost as soon as he tries to take it off, and Izuku's giggle makes him blindly kick out and connect with the metal brace on his boot. "Bitch."
Izuku laughs harder, and reaches out to help.
Soon, Katsuki is down to just his underwear and the bodysuit that makes up the upper half of his hero costume. It's form-fittingly tight, to appear seamless with the rest of his costume.
Izuku looks enraptured, as if it were the first time he'd seen Katsuki dressed only in that. Not as if they'd gotten buck-naked every day together in the locker room or anything.
"What?" Katsuki frowns, reaching back to tug the nylon down and cover the curve of his ass. Izuku licks his lips, and Katsuki feels himself blush the longer he stares.
Izuku steps forward again and lays his hands against the side of Katsuki's upper thighs. He's sweaty all over, only partly because of the heat coming down on him fast, but Izuku doesn't seem to mind as he traces the curve of the bodysuit with his thumb, until it disappears between Katsuki's legs.
"You're beautiful." Izuku beams as he says this, smile wobbly and eyes bright.
"You're so fuckin' embarrassing, fuck you."
With a laugh, Izuku lifts him up again, curling his legs back around his waist.
"Tell me if anything hurts, okay? I—" Izuku interrupts himself by kissing Katsuki again. "It's been a while."
Their hips grind together, and Izuku's leg rubs just right against Katsuki's dick.
"F-fuuck… you've done this before?"
Izuku goes red in the face, even more than before, and ducks his head. "I-I mean. Yeah." Then he frowns, though it's more hesitant than anything else. "… is that okay?"
Katsuki rolls his eyes. "It's whatever. It's fine." He tugs Izuku back down for a kiss, but Izuku stops him with a gentle grip to his shoulder.
"Are you sure? We should probably talk about this more— I don't wanna pressure you."
"You are literally between my legs and I'm leaking all over your fucking knee guard." Katsuki clamps down, and there's a slick noise that makes him grimace. "Yes, I'm fucking sure."
Plus… having someone who knew what they were doing didn't sound half bad. Less for Katsuki to worry about. All he wanted was something up his ass right fucking now. Right now now.
"Hurry up," Katsuki groans, head falling back.
Izuku's hands press against Katsuki's hips again, holding him steady as he started to grind against the leg still caught between his thighs.
Gentle fingers prod at the waistband of his bodysuit, slipping beneath just to ease the elastic from his skin. It feels good, just that, and Katsuki isn't sure how he's meant to last when Izuku finally gets inside him.
If the nerd would just hurry the fuck up.
Katsuki shoves at Izuku's arm, and is obediently set down again. He drops to his feet and steps up onto his toes, leaning over against the wall to stick his ass out. He has to clench his hands into fists to resist immediately shoving them inside his hole. He knows his ass is already ready for it— he could take a fucking baseball bat at this point.
"Fuck— okay, please Deku." Katsuki pants, spreading his thighs wider. Hopefully the view entices the nerd. "Just do it, I—"
Katsuki feels a line of pre drool from his dick, through his fucking bodysuit, and roll down his thigh. Fuck it's so gross and sticky a-and hot. "I can take it, just… fuck me. Fuck me, alpha, fuck me—"
Izuku hustles forward, shushing him. "I've got you, Kacchan." He promises, voice steadying.
Izuku drops down to his knees, and Katsuki tilts his head down to watch him from between his own legs. "The fuck are you do-ooohhhh fuuuuuuck."
Izuku drags his tongue across Katsuki's rim, gathering the slick on his tongue to greedily swallow down. Fuck that's— that's…
"D-Deku," Katsuki gasps, keening as Izuku does it again, wriggling the tip of his tongue against the fluttering rim. It breaches, just barely, and Katsuki's knees nearly go out.
"That's f-fucking, oh god, Deku," Katsuki can't stop the debauched noises sprouting from his lips. "That's dirty, y-you dumbass."
"You taste so good, Kacchan," Izuku pants against his skin, dipping lower to lave his tongue across Katsuki's perineum. A growl rumbles through his chest, pleased, and it rocks straight up Katsuki's spine to make him bare his neck— though Izuku can't see it.
Izuku continues lapping up the wet that readily spills out of Katsuki's ass, and Katsuki continues falling apart until he's nothing but whoreish moans and the heat building in his gut.
His mind starts going blank as Izuku presses his lips to his entrance and shoves his tongue in as far as he can reach, mapping out every inch he can.
Katsuki goes crazy when a finger comes up to join it. He rocks forward, hands sliding down the wall as he tries to find purchase on it. The finger just barely goes in alongside Izuku's wiggling tongue, but that's still more than Katsuki had ever had.
"You're so g-good at this," Katsuki moans, awed.
Izuku responds by sticking his finger in further and curling it until it presses soundly against Katsuki's soft, slicked inner walls. He brushes against something inside Katsuki that makes him jump, thighs slamming together to clamp down on nothing.
"Shit!" Katsuki yelps, nearly losing his balance. Izuku fully palms one of Katsuki's asscheeks to hold him up, too bewitched by the taste of Katsuki flooding his tongue to let him drop away.
That heat in Katsuki's gut continues to build and build, until Izuku curls his finger again— just once more.
Then, it crescendos and Katsuki's resulting scream is choked and garbled as it rocks through his entire body in waves.
His cum splatters against the wall as he rides Izuku's tongue, fully wiggling his hips to get more of it inside. Izuku groans along with him, briefly pulling away from the hole to place an open-mouthed kiss against the plush curve of his ass.
Katsuki's vision is a little blurry as his head drops again, but he still has a perfect view of Izuku palming himself through his pants, visibly hard even through the loose-fitting material.
He can't even think of anything to say in the aftermath, still shifting his weight from heel to heel as the vestiges of his orgasm rock through him.
His cock is still hard.
Izuku shifts forward and prods his tongue at Katsuki's hole again, and Katsuki tenses with a huff. "D-Deku…!"
Izuku eats him out again, just as eager as before. It's as if he's become addicted to the taste of Katsuki's slick, but Katsuki could honestly say he was addicted to the feel of Izuku's tongue at his rim.
It feels good— so fucking good— but…
"Deku, more." He felt so empty inside, and his hole kept fluttering around Izuku's tongue, greedy and impatient for something that Katsuki isn't sure of yet.
Izuku takes Katsuki's words into consideration for a moment, and then presses two of his fingers into the wet dripping off of Katsuki's sac. He massages it into the tender skin, mostly to lubricate his fingers, and then slowly slides them into Katsuki's ready orifice.
Izuku drops back onto his calves to watch as Katsuki's body swallows him down, and there's a pleased rumble sounding through the air, a pleased growl. It sends Katsuki's already careening mind straight into orbit.
"Good omega," Izuku praises. "I'll take care of you. Do you like it when I touch you here?"
At the question, he prods that good spot inside of Katsuki again. Katsuki bucks backwards into Izuku's palm and grinds down, to get every last inch of Izuku's fingers inside.
"Yesss," Katsuki's hisses, shoving his fist against his mouth so he has something to bite down on. "More, more, more— Deku, don't fucking stop!"
Izuku rewards him by thrusting in faster, until there's a grossly wet noise sounding with every pass of his prostate. Katsuki can't find it in himself to care, or be embarrassed, not when he's so fucking close again.
Izuku's tongue comes back, drinking down the build-up of slick on his knuckle, and he grazes across Katsuki's stretched hole.
Katsuki cums again with a trembling whine, cock weakly jumping as it spills more of his seed down the wall. He'd never felt so damn good in his life, with Izuku two knuckles deep up his ass and lapping up his slick like nectar.
Maybe he'd been missing out after all, with all this omega bullshit.
His knees are too weak to hold himself up anymore, and Izuku helps him to the floor to catch his breath, arched on his elbows and knees.
Izuku leans down too, covering Katsuki's body with his own to kiss all along his shoulders. He leaves a hickey here and there, and pauses at the scent patch that still clings to Katsuki's neck.
Katsuki watches as his eyes dilate, black pupils blowing wide to almost overtake the pretty green irises.
Katsuki's still catching his breath, but he claws at the patch with a grunt and rips it off in one swoop like a bandaid.
"Might as fuckin' well," he snorts, throwing the thing away. It was moist with sweat and the natural oils from his scent gland, but it had served its job well.
As soon as it's off the gland, Katsuki's heat-addled scent mixes with the smell of his slick and arousal. They're similar, but the pheromones add a bite to the air that makes Izuku bury his face firmly in Katsuki's neck and suckle on the scent gland as if it tasted even better than the slick he'd feasted on moments prior.
Katsuki goes down flat against the floor with a weak moan as Izuku drinks his fill of Katsuki's scent and taste. His cock grinds against Katsuki's ass, catching between the cheeks as he spreads them with palms against the fat of it.
Teeth bite down, but don't pierce the skin. Katsuki's entire body rolls with his resulting shiver.
"Fuckin' vampire," he grumbles, but doesn't shove Izuku off.
Instead, their bodies rock together as Izuku basically uses his ass to get off. He's still fully dressed, but his dick fits well between his ass as he ruts against it.
If Izuku makes him cum a third time just doing that, Katsuki isn't sure what he'd do. Marry him probably.
But Izuku gives him a break, pulling up with a heavy sigh. He inhales, licking his lips as he looks everywhere but Katsuki. Then, he rolls off to help Katsuki back to his knees, then to his feet.
"C'mere," Izuku says, holding both of Katsuki's hands in his own. "Bedroom."
It's rare that Izuku speaks in half sentences and not full paragraphs at a time. Even more rare when his voice has that husky gravel in it, too.
Katsuki stumbles after him, wide-eyed, as Izuku leads them out of the living room, finally.
"You really don't have a nest," Izuku mumbles as he eyes the empty bed. He sets Katsuki down atop it, and reluctantly ducks away from Katsuki pawing at his chest, to circle around the room instead.
He shoves himself in Katsuki's closet instead, to steal what soft things he had hid away in there: extra futons, blankets, some pillows that were getting lumpy. An All Might plush.
Izuku tosses it all on the bed, nearly burying Katsuki in it, and promptly ignores Katsuki's still quivering form in favor of playing around in the sheets.
"Deku," Katsuki grunts. "I don't need a nest."
"You do." Izuku doesn't even look at him as he says it, fluffing out the pillows as best he can.
He shoves the multicolored mess this way and that, until it forms a lump of something that almost resembles the ready-made nests that Katsuki sometimes sees in magazine ads.
It's almost spilling off the bed, but Izuku seems satisfied by the sturdiness of it as he hooks one knee over the stout walls.
When he's inside, legs crossed, he holds his arms out to Katsuki to usher him in. Katsuki goes, begrudgingly, and takes Izuku's hand when his knees knock against the edges of it.
Izuku tugs him close, chest to chest, and presses a gentle kiss to his neck. Right where his scent was strongest.
"This is my first time building one but… I'm not letting my omega go through his heat without it. We'll build a better one later, okay?"
Something funny wriggles in Katsuki's chest at the thought and he feels enamored and wanting all at once. My omega, he'd said.
He hides the stupid expression he gets, matching Izuku's pose by shoving his head into the curve of his neck.
"Yeah, fine."
Though they've calmed a bit in the lull, Katsuki can feel himself getting wet all over again. His belly feels tight and aching, though he still craves something inside. How fucking irritating.
Izuku's warm palm slides across Katsuki's belly, as if Katsuki had said it out loud. He rubs gently, until Katsuki goes lax and splays fully out across the nest.
It was a pretty sterile nest, smelling only of Katsuki, his detergent, and what little bits of Izuku it was absorbing the longer his alpha sat in it.
He felt so comfortable, though. So safe. And Izuku was looking at him as if all that mattered in the world was Katsuki being happy and satisfied.
Being an omega was fucking awesome, what the hell.
Katsuki can feel his head going hazy and clouded again, almost all at once as Izuku growls again. It's meant to comfort, vibrating across Katsuki's skin as Izuku scoots closer, but all it does is reignite the arousal in his gut.
Katsuki spreads his legs and cups his fingers against his erection, still throbbing with need beneath the bodysuit. He should've taken the damn thing off before he got in the nest, but whatever.
He curls his fingers beneath it and tentatively strokes across the sensitive skin of his cock. It immediately makes him jump, unused to the stimulation, but the touch left him tingling.
Izuku watches, until Katsuki has shoved the bodysuit out of the way and wrapped his palm fully around the curve of his length.
Katsuki almost forgets he's there, chasing the pleasure himself.
His stroking has a bad rhythm to it, as he gets overstimulated with almost every other thrust. He lets go more often than not, letting it fall back on his tummy and leave a wet puddle that's hard-pressed to soak into the already soaked nylon.
"Let me?" Izuku fits himself between Katsuki's legs and wraps his hand around Katsuki's, fitting it back against his length.
Katsuki gladly lets Izuku take the reins. The added heat from his palm makes him fall flat against the nest, though he quickly sits up again so that he can watch. It's oddly erotic, the way their fingers tangle as precum drools down the tip of his cock.
Izuku makes him stroke faster than he can handle, almost.
His thighs shake with every pass of the sensitive cockhead, followed by a punctuating moan every time Izuku twists, just to make sure Katsuki drowns in the delicious friction of it.
"D-damn, this feels so fucking good."
Katsuki had, admittedly, also never jerked off much. Never saw the point but, shit. Now he knew why people were always going on about it.
Every time Katsuki tries to let go, almost fearful of the onslaught of pleasure, Izuku eases him back with a firm hand.
"That's it," Izuku coos, gentle. "Stroke just like that. You're so pretty, Kacchan."
"Sh-shut up," Katsuki whines, hips rutting into the suction that their closed fists have created, wet as it is. "Go faster."
Izuku strokes him faster, and Katsuki's hand falls away. He smears the precum across the nest, before absently lapping it from between his fingers. Izuku's grip tightens at the sight, not painfully, but it makes Katsuki twist away from the stimulation even though his body wants more.
"Why are you so sensitive?" Izuku murmurs to himself, awed. "Are your heats always like this?"
Katsuki stays damningly quiet, biting his lip. Izuku stops jerking him off, eyebrows furrowing. Katsuki whimpers at the loss, but Izuku keeps him from thrusting up into his fist with a firm hold to his hip.
"Kacchan," Izuku starts slowly, confused. "When was your last heat?"
"None of your damn business."
Katsuki just wants him to move, to keep feeling good. But Izuku pulls away fully, and Katsuki feels real tears spring up at the corners of his eyes. Shit.
"Fuck, okay. Fine."
Izuku lifts a brow. "Well?"
Katsuki reaches down to jerk himself off, but Izuku grabs him by the wrists and shakes his head.
"Fine! When I was like a kid, or whatever. I don't have heats. Just fucking… keep going, please. Alpha, please."
Izuku looks completely troubled at the new information, but he lets go of Katsuki's wrists.
Katsuki immediately tries to stroke himself off the same way Izuku had, but it's not as good. It's bad even, when Izuku pulls away from touching him at all.
He looks lost in thought, troubled, and he's ignoring his omega.
"Fuck, don't be mad." Katsuki rocks his hips, and then rolls over so that his ass is to Izuku. "I— I can still take your dick, okay? I'll be good, just fuck me, fuck meee— shit!"
He accidentally lets go of his cock again, just on the edge of orgasm. It feels too good but he can't force himself to stay in the right position, with the right pace.
More tears, frustrated this time, well up and spill, eager to please his alpha and to finally get satisfaction.
"I'm not mad, Kacchan. Of course not." Izuku shuffles forward to mount Katsuki, trapping the latter's legs between his own. Just like before, his cock catches between Katsuki's ass and makes him keen. "I'm just worried about you."
"I'll be good, I'll be good," Katsuki whines, lost in the feeling. He needed his alpha inside, right fucking now.
"You are good," Izuku promises, nuzzling his head down. He scents at the back of Katsuki's neck, tilting his head up to wipe away the tears. "Your alpha is gonna take care of you, alright? Let me take care of you."
"Pleaseee," Katsuki begs, and then arches his ass up when Izuku pulls him by the hips. Like this, face down, he's fully presenting like a needy little omega should.
He isn't completely bare to Izuku's gaze, but it's close enough, and Izuku spreads apart his ass cheeks just to see how his bodysuit catches between and beautifully outlines his throbbing cock and aching hole.
Izuku murmurs a soft, "Hold on."
With one hand, he rips his hero costume off and tosses it to the outskirts of the nest. Katsuki wiggles towards it as he catches the scent, but Izuku quickly circles his hand in front of Katsuki's face, letting him scent directly at the gland there instead.
Katsuki presses his lips to it, sucking hard just like Izuku had to his neck earlier. It satisfies some part of his primal brain and makes him go limp, ready to take what his alpha gives.
Izuku, in the meanwhile, has begun stroking himself off. He's already the hardest he'd ever been in his life, but he needed to get himself lubed up and ready. Katsuki was so sensitive, too… It'd probably be intense for him.
Izuku mutters all of that under his breath, but Katsuki doesn't give two shits. Not when he crawls forward and presses it against Katsuki's prepped hole.
"Remember what I said earlier, Kacchan." Izuku orders, voice cutting through the fog in Katsuki's brain. "Tell me if it hurts."
Katsuki pops off of Izuku's wrist, laving it one last time with his tongue before he nods his head. With that, Izuku pulls his wrist away to focus on Katsuki's ass. He's still fingered open, dripping copious amounts of slick that still coats Izuku's tongue.
The heat seems to have finally got to him, leaving him pliant all over.
He's angled so that most of his weight rests on his shoulders and his knees, but he's still able to peek at Izuku through his lashes, mouth dropped open as he lets out soft, panting moans every time Izuku touches him.
Katsuki's breath hitches as Izuku's cock catches at his rim, prodding once or two before it slips in easily. Izuku goes slow, stopping every inch or so, for which Katsuki is grateful.
It's intense.
The stretch burns almost, but it doesn't hurt. Every time Izuku stops to let him get used to the penetration, Katsuki wheezes out the breath he's holding. He's so lightheaded, so overwhelmed, and Izuku purrs at him when he starts getting too lax, hips falling to one side.
His hold is solid, but not mean, as he straightens Katsuki again and leans down to rumble in his ear, "Show me what you want, my omega."
At this, Katsuki throws his head back and moans. He shoves back on the length in his ass, until it goes in too soon too fast and Izuku is balls deep.
But it still doesn't hurt. His hole flutters, bearing down on Izuku's girth, and the both of them groan once their hips fully meet.
The grip Izuku has on his waist tightens, but he doesn't stop Katsuki from taking what he needs.
And Katsuki takes, immediately going from slow, tender thrusts to riding Izuku's dick like it's the last thing he'll ever do.
He shoves his hands against the nest, fisting his fingers in the sheets, and grinds back until he can feel the beginnings of Izuku's knot start to swell.
"Dammit." Katsuki grunts, losing his rhythm as the pleasure gets to be too much. God dammit. "Fuck me!"
Izuku growls, picking up the slack. He lifts one of his legs and plants it firmly for better leverage, and thrusts in harder. Katsuki reaches back blindly, and Izuku keeps him steady by letting their fingers tangle, leaning down.
They kiss, and it's messy and sloppy and so fucking good. Katsuki moans with every thrust that bows his back and makes him zero in on the increasing girth as the base of Izuku's cock.
He, of course, knew what a knot was but… It was getting so big so fast. Would it even fit?
Katsuki snaps his teeth when Izuku pulls back so far that he nearly slips out, and tugs Izuku forward again by the grip he has on his hand. "Inside, alpha."
Izuku laughs shortly, breathless, and presses back in deep.
Katsuki gets herded forward, until he's up against the edge of the nest, and clings to it as Izuku restarts the pace. He can feel it battering his insides, stretching him full and keeping him taut as Izuku angles for that spot that makes Katsuki see stars behind his eyelids.
Izuku reaches forward to gather Katsuki up, arms wrapping around his shoulder so he can bury himself in the needy omega scent. Their skin slaps together, mingling with the breathy moans and groans each of them makes.
Katsuki's vocabulary devolves to nothing more than, "Yes!" and "More, more, more!" and each time Izuku obliges, rolling and grinding his hips until, finally, the knot starts to breach inside.
It hasn't reached its full girth, but it's still a sizeable difference compared to the rest of his cock. Katsuki spreads his legs wide to accommodate for it, eyes squeezing shut tighter with every extra inch that pries his sphincter wider and wider open.
Then, with a harsh gasp from Izuku, it pops inside.
"Fuuuuck." Katsuki's entire body goes loose at the feel. He goes limp across the edge of the nest, and Izuku tugs him back so that he can purr— holy fuck he was purring— to his heart's content.
Izuku's praises go in one ear and out the other, but Katsuki comes back to himself as Izuku murmurs a soft, "Good omega, you take my knot so perfectly. Feel that?"
Izuku's thumb feels along the stretched taut rim and Katsuki tosses his head back as another jolt of pressure rocks through him.
Katsuki reaches his hand back, to feel, and his fingers come back dripping wet with slick, with his need.
"Fuck."
He hasn't cum yet, but it's as though he's on the precipice of it, waiting for Izuku to do something.
Izuku can't thrust anymore, caught like that, but he can grind his hips against Katsuki's, brushing his cockhead right up against his prostate.
The little rocking motions aren't enough though. Katsuki lifts his hips away, trying to tug Izuku out for those full thrusts again, but Izuku holds him unyieldingly firm.
"I can't, nnngh—" Katsuki trembles, shaking his head. "I n-need…"
"Hold on, darling," Izuku grunts, and scents along Katsuki's neck. Katsuki twists his head, fully exposing his scent gland, and Izuku rakes his teeth across it. "I'm gonna— gonna cum if I'm not careful."
Katsuki only needs one glimpse of a mental image of it before he's writhing, grinding back to meet Izuku's halted rutting. He wants to be completely flooded by it, wants to be filled up by Izuku's cock and his knot and his cum.
"Inside!" Katsuki cries out, "Cum inside me, alpha!"
Katsuki's insides bear down hard, as if he's trying to milk the seed right out of Izuku's dick. Slick eases the way as he jolts forward, trying to pop the knot out to push it in again, but Izuku grabs him by the shoulders and shoves him flat.
He's got Katsuki pinned like that, cock shoved in the deepest it could go. Trying to pull away seems to have set off some instinct in Izuku because his teeth are bared when Katsuki leans back to look at him.
"Mine." He snarls, and bites down on Katsuki's shoulder.
Katsuki moans out a garbled, "Izuku!" and cums for a third time that day, entire body on fire.
It washes through him, almost like he's being drowned, and then he can feel Izuku still growling against his neck as he shallowly thrusts through the influx of slick coating his cock.
Izuku rears up and slams their hips together one last time, teeth still bared directly against Katsuki's skin, and cums so deep in Katsuki that it feels like it went straight to his colon. Holy fuck.
Katsuki twitches with every spurt, burying his face in his nest to muffle the strange chirping noise he keeps making.
Izuku laps at the red bruise forming on his skin, where he'd bitten down, but the skin hadn't broken.
Then, with a grunt, he rolls them onto their sides, away from the wet spot in the middle of the nest. Despite them being wholly uncovered, Katsuki felt so warm and comfy that he nearly falls asleep right then.
"Kacchan," Izuku sighs, pleased, and rubs his palm across Katsuki's belly. It's almost as warm outside as the seed spilled inside. "You were so good."
Katsuki hides his red face against his arm. But he does accept it as Izuku scents him all over, until the satisfied omega smells only of him and his slowly receding heat.
It would come back later, probably just as intense, but Katsuki would be okay as long as his alpha was there to ease him through it.
---
Later, when they've unlocked from one another, Izuku leaves and comes back with water and a fresh blanket. They briefly scent again, neck to neck, and Katsuki exaggeratedly turns his nose up as Izuku insists on cuddling him tight, front to front this time.
He does accept it though, napping most of the day away.
But, Katsuki's mind eventually clears enough for him to turn to Izuku with a glare.
"How did you know I was an omega?" Katsuki asks, frowning. "I was fucking good at keeping it under wraps."
Izuku laughs, forceful and awkward. It continues so long that Katsuki lifts his head and glares at him hard, reaching out to flick him across the nose.
"Ow! Kacchaaaan," Izuku whines, rubbing the reddening spot.
"Answer or die." Katsuki heats his palms, popping off harmless sparks. Izuku doesn't flinch away, but does placatingly hold up his hands.
"Well…" Izuku sits up in the nest, untangling himself from Katsuki's legs.
Katsuki retangles them when Izuku settles, back against a sturdier part of the sloppy nest, and shoves his face against the now-exposed part of Izuku's waist.
Izuku laughs as Katsuki steals heat from him, and places a hand across the curve of his head.
"Well," Izuku repeats, rolling the word across his mouth. "You told me."
"I did fucking not."
"You did!" Then he laughs again, voice gentling. "Showed me, actually. I was there when you first presented, and your heat hit you. You were so out of it."
Katsuki stills, arm pulling away. Izuku pauses in petting, in case Katsuki pulls back all the way, but Katsuki stays pressed body to body.
That felt like forever ago. Middle of puberty and bam second puberty. Katsuki only remembers his second heat because his doctor had given him low-grade suppressants so he didn't fuck up his body too soon.
Izuku continues petting. "It was really scary. I'd never seen you so… unsure. So passive. You didn't even yell at me when I had to carry you back home."
Katsuki turns up his nose, but doesn't bring up how fucking submissive he had been when Izuku was railing him out of his mind.
Izuku seems to pick up the sentiment anyway, face going pink as if they hadn't just had sex. Who had been the virgin here??
"It was different!" Izuku argues. "You didn't know what was going on, and it was just the two of us. And I wasn't used to being the leader back then."
"You still don't know shit about being leader," Katsuki says, haughtily.
Izuku laughs again, softer, and drifts his touch lower to hug Katsuki close. "You know, Aunty Mitsuki says that you set off my rut after that."
"We did not fuck that early. Shut the fuck up."
"We didn't!" Izuku chokes out, almost yelling. "I was home when it hit. But when I brought you home, she said that she could smell it on me."
Hmph.
"Guess that just makes me the strongest fucking omega ever. I beat your own instincts into following after me." It's almost poetic.
Izuku pffts, tugging the blanket further up to cover them. He smooths it across Katsuki's skin, thumbing at the lingering ache in Katsuki's hips.
"You are the best omega, Kacchan." Izuku nods, readily.
He doesn't continue after that, and Katsuki does not get flustered. He hides his face against Izuku's hip again and grumbles under his breath.
"Yeah, well… you'd better take responsibility. Cherry-popper."
Izuku splutters, embarrassed, and Katsuki cackles at him until Izuku pulls him close to shut him up with more kisses and scenting.
The vestiges of his heat still lingered beneath his skin; Katsuki could feel it simmering, slowly building again.
But he couldn't argue that he was satisfied down to his very core. Izuku leans down and presses a kiss to Katsuki's forehead, mumbling something about getting them more water and snacks in a moment.
Katsuki just squeezes him close, trapping Izuku there as he relaxes further.
He may be the best omega, but his alpha was pretty great, too.