#dkbk

tl;dr: deku is a surprisingly aggressive alpha

please don’t expect quality snsjd

— Like something straight out of Aizawa’s nightmares, everyone in 1-A presents within weeks of each other. Raccoon Eyes goes first, flooding the classroom with fresh alpha pheromones +

at the start of the semester; from there people start presenting almost weekly in a bizarre, hormonal domino effect.

Surprisingly, Katsuki presents last and presents as an omega, of all things—the only one in the class.

Katsuki can’t say he likes it; it’s inconvenient as shit.

But it wouldn’t bother him if all the alphas in his class hadn’t collectively lost their minds.

It isn’t obvious at first: Shitty Hair throwing an arm around his shoulders in crowded halls of UA, Half n Half bastard purposely standing between Katsuki and the street +

whenever they tag along on patrols. Shit Katsuki can usually ignore.

But then there’s Deku.

The shitty nerd’s presentation was arguably more controversial than Katsuki’s. Classic Deku, stealing his thunder like it’s a biological imperative.

It’s not that people are too surprised Deku presented as an alpha... It’s just that he’s a surprisingly *aggressive* alpha. And somehow he’s gotten it into his thick, nerdy, alpha head that Katsuki is his responsibility.

But Katsuki doesn’t lash out.

He doesn’t yell (much) when Deku growls at Kaminari for calling him “Kacchan”, doesn’t blow him up for leaning forward in his chair and inhaling deep near the nape of Katsuki’s neck, because he’s better than that. Or he’s trying to be, but lately +

the nerd is really fucking testing him.

“Kacchan isn’t feeling his best,” Deku insists—which is bullshit because Katsuki feels *fine*—glaring Shitty Hair down. “He should provide support while I rescue the victim and you cover us.”

Katsuki’s palms are already popping +

with explosions, temper rising at being talked about like he’s not standing *right there*, but before he can even tell Deku off Kirishima is butting in.

“Bakugou’s fine,” he says with a smile that looks plastered on. “He’ll lead. I’ll provide support, and you cover us, dude.”

Normally that would be Katsuki’s cue to tell these knot-heads to shut up and follow him already, but the shitty nerd might be on to something. Katsuki’s sweating more than usual and they haven’t even started the training exercise yet.

He doesn’t know how to feel about seeing the two sunniest losers he knows like this: teeth bared, eyes narrowed, and postures tense as they face off.

Aizawa and All Might do nothing to stop it. Something about the class hierarchy having to “settle naturally” or whatever.

Katsuki doesn’t need a hierarchy to tell him where he stands. The only place Katsuki belongs is at the top, and all this instinct shit is just a distraction.

“We’ll go with Shitty Hair’s plan. Let’s get this over with,” Katsuki says, cutting through the tension.

He doesn’t wait for a reply before striding forward. His gauntlets feel like they weigh a thousand pounds, and there’s sweat beading his hairline, darkening the edges of his mask, but he tries to act unaffected. He can make it through class; he’s been through worse and still +

come out on top.

Katsuki uses his explosions to propel himself through the air, navigating the rocky terrain of Gymnasium Gamma, Deku close on his tail and Hair-for-Brains following them on the ground.

He can feel Deku’s gaze like a physical touch on his back +

as he lands near the victim—a poorly sewn together rag doll—who is trapped on the edge of a cliff beneath a boulder. He stumbles as his boots touch the ground but recovers before Deku can do something annoying like reach out to him.

Kirishima shows up a second later, +

and Katsuki is about to start barking orders when Deku gets right in Kirishima’s face, looking furious.

“I told you Kacchan isn’t feeling well,” he snarls, shoving Shitty Hair back a step. “He can barely fly.”

Kirishima doesn’t hesitate to shove back, caught up in the +

frenzy of alpha aggression.

Before Katsuki can even fully comprehend what’s happening, they’re snarling and grappling with each other. Kirishima is in unbreakable mode and Deku has activated Full Cowling, green sparks leaping off his skin.

The air is heavy with the scent of angry alpha and Katsuki is starting to get lightheaded, high off it.

The first trickle of slick that slides out of him fills Katsuki with a sense of dread, but he can’t help it; two alphas are fighting over him and it’s making him *wet*.

tbc ???

Deku’s head whips around so fast Katsuki wouldn’t be surprised if he gave himself whiplash, eyes sliding from Katsuki’s face to his hips.

Katsuki’s face burns with the knowledge that Deku can *smell* him, and it isn’t long before Kirishima gets distracted by the scent too.

Even worse, the attention of two powerful alphas has the slick coming faster, forming a damp patch on the front of Katsuki’s pants. If Katsuki were a lesser man, he might’ve tried to hide. Instead he stands his ground.

If he makes a move to run, he has a feeling they’d be on him in seconds.

Green sparks fly off Deku, and Katsuki can tell he’s increased the percentage of OFA by the way he tosses Kirishima to the side like a rag doll.

It shouldn’t be hot.

Katsuki tells himself it’s not, but his body betrays him, knees weakening as Deku stalks closer.

Katsuki takes one step back, then another, making a face at the way his wet pants cling to his thighs. His back hits rock, and like every cliche in the book Katsuki finds himself +

caged between the rock at his back and Deku’s body.

The alpha’s pupils are huge, only a thin ring of green left to halo them. Deku ducks his head just enough to almost brush Katsuki’s shoulder, inhaling close to the scent gland on his neck.

Katsuki grits his teeth and forces himself to stay standing.

“Your heat’s close, Kacchan,” Deku hums, and Katsuki shivers; he doesn’t want to know how Deku realized that before him. “You shouldn’t be out like this. It’s *indecent*.”

Katsuki glances over Deku’s shoulder. He can see Shitty Hair still in a heap on the ground. The impact must’ve knocked him out cold even though he appears fine, protected in his hardened state even unconscious. He doesn’t look like he’s getting up any time soon though, +

which means Katsuki’s on his own.

“Back up, Deku,” Katsuki practically growls, shoving Deku’s shoulder hard and definitely not getting wetter when he doesn’t budge. “Control yourself, shitty alpha. We’re still in the middle of class.”

— thinking about taking this thread in a nsfw direction

what should omega bkg have?

#nsfw — cw: intersex omegas

“You’re right, Kacchan,” Deku says, but Katsuki doesn’t trust the honeyed tone of his voice or the way he places a hand low on Katsuki’s back. And Katsuki doesn’t know exactly when it happened, but at some point Deku became *bigger* than him.

His hand nearly spans the entire width of Katsuki’s waist. “You can’t keep going like this; you’re making a mess.”

Deku gestures with his chin to the slick staining Katsuki’s pants, as if it isn’t all his and Shitty Hair’s fault.

Katsuki feels himself turning bright red all over again.

“Shut the fuck up, nerd,” he says, but his voice lacks bite. Deku’s hand on him is distracting, and this close his scent is starting to make Katsuki salivate.

He presses a muscular thigh between Katsuki’s legs, right up against his pussy, and slick seeps into Deku’s hero uniform.

The alpha doesn’t seem to care, leaning in to whisper in Katsuki’s ear, “Don’t worry. I’ll help you take the edge off, Kacchan.”

“Deku,” Katsuki says. The alpha is too close and when Katsuki shifts his weight to try putting some distance between them, the pressure against his cunt makes his toes curl. He can feel Deku’s cock, hard and heavy, where it’s pressed against his thigh.

More slick slides out of him, and he wonders if maybe Deku is right. No matter how hard he tries to breathe around the scent of alpha and arousal, his head stays foggy and his body is only getting hotter. If Deku doesn’t do something quick, Katsuki isn’t sure how lucid he’ll +

be in ten minutes.

Katsuki bites his lower lip, then reluctantly growls, “Fuck, okay. Just hurry up.”

“Good omega,” Deku croons, and it lights an unbearable fire in Katsuki, making him ache. He starts to pant, chest heaving, sweat darkening his ash blond hair to dirty gold.

As if sensing his sudden desperation, Deku presses his thigh against him harder and Katsuki moans, rocking down against it.

“Don’t call me that,” Katsuki hisses, trying to control the twitch of his hips, but Deku’s thigh feels so good between his legs, +

putting pressure right where he needs it. So good that he can’t help but keep going, practically riding Deku’s leg.

Between biting back his whines and grinding his trapped, leaking cock against the alpha’s hip, Katsuki starts to lose track of things.

Despite Katsuki’s complaints, Deku still hasn’t shut up. He keeps muttering in Katsuki’s ear while he mouths over his scent gland, mumbling fervently about what a perfect omega Katsuki is, how pretty he is, how well he fits in Deku’s hands, how he was *made* for this.

Katsuki can’t focus on any of it, too busy squirming in the alpha’s arms for more. Fuck, fuck he needs more. His stomach is cramping, pussy clenching around nothing. He’s a mess, just like Deku said, and the only thought in his head is how badly he wants Deku to mess him up more.

“What part of hurry didn’t you understand, alpha?!” Katsuki snarls. He’s pressed up against Deku shamelessly, legs spread, wet and ready. Why the fuck isn’t Deku doing something?

“Shh,” the alpha says, pulling one of his air-force gloves off with his teeth.

It drops to the ground where Katsuki’s belt and gauntlets are already discarded. He doesn’t remember Deku taking them off him (though that would explain what’s taking so damn long), but he doesn’t really care as long as Deku does something *right now*—

“You’re dripping.” Deku’s voice is caught somewhere between lust and awe. He pushes Katsuki’s pants down until they catch around his knees, fabric bunching around the knee pads. Katsuki has no idea how much time has passed, +

if Aizawa or someone else will come looking for them soon. “You want it that bad, Kacchan?”

Deku’s fingertips dip between his legs, brushing against the soft lips of his pussy, and Katsuki jolts at the feeling, gripping Deku’s shoulders and digging his nails in.

“Yeah, fuck. I want it,” Katsuki gasps, voice rough. Deku’s fingers feel huge somehow as they trace his slit, gathering the slick there on his fingers, little tingles of sensation spreading through Katsuki with every gentle stroke.

He’s practically shaking with need, seconds away from outright begging, when he sees Kirishima stir over Deku’s shoulder.

Katsuki’s eyes go wide as Shitty Hair shifts on the ground with a groan, clearly struggling towards consciousness.

Fuck, why *now*?

Katsuki almost wants to cry in frustration, or maybe blow some shit up.

“Deku, wait,” he says, begrudgingly, “Shitty Ha—ahh!”

Deku pushes two fingers inside without warning, and Katsuki’s toes curl at the sensation, mouth hanging open in shock.

Oh fuck, that feels *good*. So fucking good. It feels like an itch inside him is finally being scratched.

Katsuki slumps forward against Deku’s chest as Deku starts to finger him mercilessly, too blissed out to care about the embarrassing wet noises Deku’s fingers make as they slide in and out of his dripping pussy.

“Hm? What was that, Kacchan?” Deku asks. The slightly teasing lilt to his voice tells Katsuki he knows exactly what he’s doing.

Damn nerd.

“Kirishim—ah, shit!” Katsuki presses his face against Deku’s shoulder, trying to muffle his moans. He needs to get himself together, but Deku’s fingers are rubbing a spot inside him that makes Katsuki’s eyes water and his legs shake. “F-fuckin’ stop! He’s gonna see.”

Katsuki lifts his head, peering over Deku’s shoulder. Shitty Hair is finally starting to push himself off the ground. Any second now he’s going to look up and see Katsuki with his pants around his knees, slick dripping down his thighs, +

Deku’s thick fingers sliding in and out his greedy pussy.

“Then I guess you better cum quick, Kacchan.” Deku’s voice is as low as Katsuki’s ever heard it, intimate like he’s sharing a secret, mouth pressed close to Katsuki’s ear.

Katsuki would never admit it, but he lets out a small omegan whine, cock leaking where it’s trapped between their bodies. He starts pushing back onto Deku’s fingers then rocking forward to grind his cock against the alpha’s abs.

His jaw goes slack at the pleasure, pink lips parting around breathless little moans.

“Or maybe,” Deku says, and now he sounds breathless too, like there’s nothing hotter than being three fingers deep in Katsuki’s cunt, “you like being watched.”

“S-shut up. I don’t,” Katsuki gasps.

When he finally gathers the courage to look over Deku’s shoulder again, Kirishima is fully conscious and no longer in unbreakable mode.

Katsuki’s heart pounds, pussy clenching tight around Deku’s fingers while his cock drools precum.

Deku’s chuckle in response sends a stab of heat straight to Katsuki’s gut.

“Liar,” the alpha whispers, working another finger inside. It’s a tight fit, but when he wiggles his finger in past the knuckle it burns so good. Katsuki spreads his legs more, giving Deku room to work.

“You’re leaking so much slick that your pants are drenched, Kacchan. Do you want to be caught that bad?”

He shakes his head, blush burning so hot he can feel it spreading to the tips of his ears and along the back of his neck. Deku’s lips brush his ear, and he shivers violently.

“It looks like you do, omega.”

Deku thrusts his fingers deep and spreads them, imitating the inflation of a knot just as Katsuki glances up and meets Kirishima’s shocked eyes. The alpha’s face is as red as his hair, mouth ajar in disbelief.

Katsuki can see that Shitty Hair is hard, cock straining against his pants.

And just like that he cums. Katsuki’s body tenses, vision going blurry as he squirts, drenching Deku’s hero uniform and his own. He can’t tell if he’s making noise or silent, too caught up +

in the pleasure flooding him. It feels like it goes on forever.

Just when he starts to go limp against Deku’s chest, the alpha slides his fingers out of Katsuki’s pussy (despite the omega’s needy whines) and uses his wet hand to jerk his cock.

It’s too much, Katsuki’s body already trembling with oversensitivity from his last orgasm, but Deku is ruthless, jerking him hard and fast until Katsuki can feel another climax building.

He glances down at Deku’s hand wrapped around his cock, +

the way his palm covers it from base to head so that just the red, leaking tip peeks out over his fingers. Katsuki’s cock is big for an omega, but apparently that’s nothing compared to Deku’s alpha genes.

“Deku, fuck, I can’t,” he groans, tears gathering in his eyes as +

the pleasure builds higher and higher until Katsuki is afraid of what’ll happen when it finally crests.

“Shh, just let go, Kacchan,” Deku says, pulling off his other glove and reaching back with his free hand to stuff Katsuki’s pussy full again.

The omega drools a little as he’s suddenly fingered; it feels so good. “Your alpha will take care of you.”

It finally hits Katsuki then that this isn’t about sharing him with Kirishima; this is about showing Shitty Hair who he belongs to.

Deku rubs his thumb over a sensitive spot on the underside of Katsuki’s cock, and just like that he’s shaking through another orgasm. He bites down on Deku’s shoulder to muffle the pathetic little whines and yips he makes as his cock spurts clear, sticky fluid between +

their bellies.

Deku keeps fingering him as he cums, spreading and curling his fingers to imitate a knot as Katsuki slowly comes down from the pleasure.

“Good boy, Kacchan,” Deku whispers as Katsuki slumps forward in his arms, too fucked out to bother telling Deku to shut up.

“Good omega.”

It takes Katsuki a few minutes before his head clears and he gathers himself enough to shove Deku away and pull up his pants. Shitty Hair must have left at some point, which Katsuki is grateful for.

He won’t be able to look Kirishima in the eye for at least a week after this.

“We should probably head back to the dorms,” Deku says. Katsuki opens his mouth to argue, but shuts it when the alpha adds, “We can’t do the exercise like this anyway.”

They’re both drenched in slick and cum, and since there’s no way Katsuki is letting the rest of the class see him like this, he begrudgingly has to concede.

“Plus,” Deku says, with a glint in his eyes that Katsuki doesn’t trust, “I’m not done with you yet.”

— fin

thanks for reading !! lemme know what you think