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Side Effects May Vary

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This is, by and far, the stupidest fucking side effect Tomura has ever had to deal with. He could handle the nausea, the cramping, the urge to devour everything in the bar and still send Kurogiri out for more.

But this!

“Make it stop.”

“My apologies, Tomura.” Kurogiri really does sound apologetic, even if Tomura could give a shit less if the man was drowning in guilt right now. “The doctor said that there is little to be done in terms of alleviating this side effect. It must simply run its course.”

“I’d rather have my fucking heat.” Tomura grits out.

“We both know that is untrue. Your heat would cause unnecessary attention and we cannot afford--”

“Fuck off!”

Tomura clears the bartop with one swing of his arm, sending pints crashing to the floor to shatter as Kurogiri stares at him with a blank expression. He doesn’t react to it at all, past simply putting down his rag and heading towards the door.

“I will fetch some painkillers and sleeping medications. With any luck, those will help you through this time.”

And then he’s gone. Leaving Tomura to stew in his own rage alone. For a moment, he considers just wrecking the place. Grabbing onto things just to watch them crumble in his grasp, leave the whole fucking room a pile of dust for the warp user to clean up when he gets back.

But when he leans forward to grab at the alcohol bottles behind the bar, thinking that destruction and drinking go nicely together, his chest brushes the wood and pain shoots through him so fast he can’t breathe for a moment.

He slams his fist with a howl, free hand flattening over his chest like it’ll help quell the ache. It doesn’t, the waves still washing over him, skin under his palm feeling hot and tight and so sensitive even the pressure of his own touch makes him want to scream.

Tomura’s so distracted he doesn’t lift a finger, doesn’t make sure he’s not grabbing, and he kicks at the bar with a snarl when his shirt falls to pieces around him.

The cool air of the bar doesn’t help at all and Tomura folds his arms around his chest with a low whine, all the fight draining out of him as he pitches forward to rest his forehead against the cold wood.

It hurts so fucking bad. It’s been hurting, since he woke up yesterday morning. It was negligible at first, barely more than an ache like he’d slept wrong. But it had only gotten worse as the day had gone on and by the time he was screaming down the phone at the useless doctor who’d caused this, he knew it wasn’t going to end anytime soon.

He can’t even relieve the pressure himself. He’d tried, holed up in the bathroom and studiously not looking at his reflection in the mirror. All it had gotten him was even more pain and a few cuts on his hand when he’d slammed it against said mirror in frustration.

“The fuck is wrong with you?”

“Go away.” Tomura hisses, not even bothering to look up as the scent of firewood and char precedes Dabi’s drawled question.

There’s a snort and the sound of footsteps coming closer.

“Who shit in your leaderboard, freak? Did the TV re-run an All Might special or--what the hell.”

The crunch of glass, the sudden stop of movement. Tomura tips his head, glares through the strands of his hair at the Alpha who’s looking between the glass and him with narrowed eyes.

“I said, go away.”

“Explains why Kurogiri told me to steer clear when I passed him on the street.” Dabi nudges a pile of shards with the toe of his boot. “But I thought--who am I to pass up an opportunity to piss off the scrawny little asshole?”

You’re the asshole.”

Not one of his better comebacks, but Tomura feels like he’s stretched so thin he might snap. Like one more pull is just going to make him rip apart. And he’s sure as hell not going to let that fucking doctor patch him back up if he does.

“Clever.” Dabi grunts, tipping his head and examining him. “What happened to your chest?”

“Like you don’t fucking know.”

“If I knew, I wouldn’t have asked.”

Tomura raises his head just enough to level the full power of his glare at the other man, though he seems largely unaffected, staring back blankly. It’s enough to make him snarl, lips lifting away from his teeth. Omega’s can’t muster the snarls that Alpha’s can--it’s more like a puppy baring it’s fangs at a full grown wolf--but he’s been around enough Alpha’s that he can copy it well enough.

Not that it matters since Dabi doesn’t seem to even acknowledge it past the hike of one brow.

“Stop fucking with me. I know you can smell it.”

Actually,” Dabi drawls, tapping a finger against the side of his nose, “I can’t smell much. Can tell people’s secondary genders, sure. But that’s more context clues than anything. Turns out burning up from the inside out fucks your sinuses.”

“Spare me your sob story.”

“Spare me your attitude.” Dabi shoots back.

Tomura growls once more before dropping his hands and spinning on the stool. It leaves him exposed, something that makes his chin drop to his chest, trying vainly to hide as Dabi’s eyes slide from his face to his neck to his chest.

And stop dead. Before widening. Tomura watches his pupils dilate, black eating up that blue until there’s little left. His mouth drops open, dragging in a breath like he’s trying to scent deeper despite his words, and the rumble that vibrates out of him is so powerful Tomura almost keens in response.

But he won’t. He’s already going to hear about this for fucking months until Dabi gets tired of mocking him for it. He’s not going to give the asshole any extra ammunition.

Except...Dabi’s not mocking him. He’s not saying anything, actually. Just standing still as a statue and staring, the only movement being his hands clenching and unclenching at his sides.

“Holy shit.” He finally breathes, after what feels like a full five minutes of silence. “Did you get knocked up?”

“No, you fucking idiot.” Tomura wishes he hadn’t shoved the pints to the floor because he’d love to launch one at the moron’s head right now. “It’s the new birth control that Ujiko put me on. This is apparently a “rare” side effect.”

He snorts.

“Though he failed to mention that it was a side effect at all, the rat bastard.”

“Uh-huh.” Dabi’s drifting closer, feet crunching up the glass as he sways, eyes never rising past Tomura’s collarbone. “So you’re...this is temporary?”

“It had better fucking be,” Tomura seethes, “or I’m going to burn this whole goddamn city to the ground.”

Dabi makes a noncommittal noise--which is strange. Usually any talk of destruction is enough to get him to chime in, albeit normally with a disparaging comment about Tomura’s plans. He’s not responding at all past the initial hum, stopping with a few scant inches between them. Tomura lifts his head, hand drifting up instinctively to protect his throat as he drags in a deep breath through his nose.

Holy fuck. Dabi is turned on. And not just a little, either. He’s pumping out so many pheromones Tomura thinks he might choke on them, the very air seeming thick with the scent. How he didn’t smell it before now is a mystery and he swears on everything that if that’s another “side effect”, he’s going to decay that doctor the second he sees him. Sensei’s orders be damned.

“God.” He lifts his hand higher, shoving the back of it against his nose as he sneers. “And you call me a freak.”

Dabi doesn’t take the bait. Doesn’t even bristle like he normally does when he’s holding back a shitty comment. Just continues to stare, barely blinking, tongue flicking out to wet his lips.

“Looks like they hurt.”

“Of course they fucking hurt.”

“Are you...are you actually producing milk?”

Yes.” Tomura hisses before pausing, grimacing before his next words slide free. “I think. I can’t--I tried and I couldn’t get anything out.”

“Figured. They look swollen. Looks like you’ve been mean to yourself.”

Tomura lowers his hand to his throat once more, letting the scent in but feeling the need to protect himself over the need to block the smell.

“What the hell else was I supposed to do?!”

He’s aware he sounds a little manic. A little panicked. But there’s an Alpha standing a foot from him putting off breeding pheromones like no one’s business and the smell alone is making his nipples ache. And he’s always thought Dabi was attractive but he’s never actually considered it as a possibility since he thought the Alpha would rather die than get close enough to touch, let alone fuck.

But now…

“Omegas produce milk for their pups.” Dabi says softly, head tipped like he’s listening for something far away, or maybe remembering something. “Really only one way to get the milk out without hurting.”

“I don’t see any pups around here.”

Dabi levels an unimpressed stare at him for a moment but can’t hold it, eyes flickering before they drop to his chest once more.

“I could.”

Tomura can’t help the snort that escapes, or the laugh that’s just a touch too mean. It’s just so fucking perfect, isn’t it? Dabi gives him shit day in and day out but the second Tomura starts leaking milk from his tits, the guy can’t offer himself up fast enough.

And people say that Omega’s are the desperate whores of the secondary genders.

“You’re joking.”

“You don’t have to say yes.” Dabi’s drifting forwards though, even if he’s offering the out. “Tell me to fuck off and I’ll get out of here. Figured it might help you though, since you keep bitching about it.”

“Oh, how charitable of you.” Tomura sneers. “Helping out a poor little Omega. Like you wouldn’t get anything out of it.”

“Not saying I wouldn’t. Just saying you can say no.”

He wants to. A part of him that never liked to share his toys, that would prefer to break them rather than let anyone else touch, wants to tell Dabi to get out. To deny him something he so clearly wants.

But it hurts. And it’s been hurting. And Tomura isn’t so masochistic that he’d be willing to make himself suffer when the possibility of relief is so close.

“Fine.” He agrees with a put-upon sigh, rolling his eyes towards the ceiling. “Whatever. Give it a shot, if you want.”

Dabi reaches for him and Tomura can’t help but tease, pushing to his feet and dodging the hands, slipping backwards. He’s answered with a growl, one lip curling up in agitation as Dabi stalks after him.

“What are you doing.”

“Being considerate.” Tomura walks back until his calves hit the couch, plopping himself down heavily and wrinkling his nose at the puff of dust the motion kicks up. “Didn’t figure it would be comfortable on the bar stool.”

Not to mention the position wouldn’t be nearly as fun. Like this Dabi has to slide to his knees--which he does easily, the movement practiced and feline in it’s grace--and it puts him between Tomura’s thighs, kneeling at his feet.

Right where he should be. Right where everyone will be once his plans go through. Once the Symbol of Peace is no more and Tomura is on the throne he’s always been reaching for.

“Might hurt a bit at first.” Dabi doesn’t seem to care about his position or what it could imply, scooting forwards until Tomura’s knees are bracketing his ribs, fingers dragging slowly up his stomach. “Bear with me. I’ll make you feel good.”

“I’m not one of your shitty one night stands.” Tomura rolls his eyes and reaches out, grabs a handful of his hair, keeping his pinky raised as he drags him in. “Don’t waste your time with useless words.”

Dabi grumbles but doesn’t shake him off, looking almost trancelike as he lets both his hands drift up, cupping around the just barely there swells of Tomura’s tits. He can only imagine they’d get bigger if he let this go on and that’s another reason he agreed--last thing he needs is Toga trying to get him into a bra or something idiotic like that.

“Just relax.”

Tomura rolls his eyes, fighting back a shiver at the feeling of hot breath washing over sensitive skin.

“Get on with it.”

He doesn’t listen--not that Tomura expected him to. There’s a short inhale, shaky like Dabi’s vibrating from his core out, and then the brush of a tongue against one nipple. It doesn’t particularly feel like anything that Tomura would want to write home about, nothing like the Omega’s in porn act like it does. He isn’t feeling the need to whine and claw at his Alpha’s back, arching and spreading his legs and begging to get fucked.

Mostly he feels bored.

“Hurry up or fuck off.”

“Stop being such a brat.” Dabi hisses, before biting at him.

“Ouch!” Tomura yelps, letting go of the hair in his grip to bring his fist down on Dabi’s head. “You asshole! I told you they were sensitive!”

“Awww, poor baby. Lemme make it all better.”

He nearly hits him again. In the face this time. Nearly opens his hand and smacks at Dabi’s ruined face with all five fingers just to make a point.

But Dabi darts forward, wraps his lips entirely around one nipple and sucks.

And Tomura...Tomura can’t breathe, let alone think.


It feels weird and good and bad and wonderful. Nothing he’s ever experienced before. There’s a deep pull from Dabi’s mouth that eases up after a moment, starts back up again after a cursory flick of his tongue. But, after a few seconds, there’s a new sensation. A tickle deep in his chest, like movement under the skin, and Dabi’s making a filthy noise around the flesh in his mouth.

Milk. He’s actually getting milk from Tomura. And...swallowing it, given the absolutely lewd sounding noises rising up in the quiet of the bar.

He wants to shove him away. Stalk back to his room and slam the door on the whole situation, pretend it never happened. But the relief is so good, so stark, he finds himself groaning and grabbing Dabi’s coat, hauling him in closer.

It spreads his legs further and Tomura can smell himself over Dabi’s pheromones now, the hot scent of his arousal. He can’t help it, probably some dumb Omegaen instinct that thinks he’s going to get mated since he’s getting his tits sucked dry.

Dabi doesn’t seem to mind it though. He’s making little huffing noises through his nose, nudging at the flesh and squeezing gently, groaning when the tickle increases and probably covers his tongue in another wave of milk.

Too much. Almost too much. It already feels much better there but Tomura is more acutely aware of how badly the other side aches now. Like relief on one side only made the other hurt worse. He tugs on Dabi’s hair, mouth falling open in shock when the Alpha slaps at his hands and snarls.

“You stupid--move to the other side, you fuck!”

He yanks hard, popping Dabi off with a wet sound, and stares for a long moment in shock at the sight of the other man’s face. He looks drunk, eyes half-lidded and cheeks flushed where the skin is still intact. There’s a speck of creamy white at the corner of his mouth, hurriedly cleared away by a swipe of Dabi’s tongue, and Tomura shudders so hard at the sight that he nearly lowers his pinky down.

Dabi growls, the sound arching high at the end in question, and Tomura--for once in his life--doesn’t tease. Doesn’t talk shit or mock him. Just guides him forward to the other nipple and whines softly when he latches once more.

Just as good. Better, maybe, since his body’s heating up, becoming more sensitive. Tomura debates for half a second before wrapping his arms around Dabi’s head, holding him in close and letting the shivers work their way through him.

He wants to get fucked. More than he ever has during his heats. More than he ever has in his life. Wants Dabi to yank his clothes off and sink into him again and again until he’s locked onto his knot and coming his brains out. Logically, he knows it’s his instincts. That none of this is his rational brain making demands.

Doesn’t matter.

Doesn’t fucking matter.

“Fuck me.” He bites out, snapping a hand down and holding it against his thigh until the fabric gives way and falls, adding more dust to the already filthy couch.

Dabi doesn’t pull back even as his hands drop, fumbling with his belt buckle for a split second before he’s shoving down and moving in even closer. He grabs ahold of Tomura’s thighs, yanking him half off the couch and into his lap, still suckling the whole time.

He’s like a beast. Like the Alpha’s of legend. Nothing but instinct and need as he swallows obnoxiously and presses the heat of his cock against Tomura’s hole. It’s not gentle, neither of them in the mood for such nonsense, and Tomura really does let out a whorish moan when Dabi grips his hips and yanks him down onto his cock.

It’s not comfortable and it’s not slow. Dabi pounds into him like Tomura’s just a hole meant to take his cock, leaving him scrambling to try and stay on the couch during the onslaught. He thinks distantly that it’s fucked, that he’s going to grab ahold with his entire hand at one point since his other hand is staying stubbornly in Dabi’s hair, holding him in close.

Like the Alpha is going to go anywhere.

The most he does is switch nipples, raising a hand to thumb at the one he’s not currently abusing with his tongue, hips still snapping forwards like he wants to fuck Tomura through the couch.

Fine by him. Tomura feels like it’s all one big orgasm, with peaks that have him choking out Dabi’s name and lows that still make his entire body shudder. He’s never felt this good before and, if the birth control wasn’t the reason he was in this situation, Tomura would wonder if Dabi had triggered his actual heat.

“Gonna knot you.” Dabi slurs around his nipple, milk and drool slipping out over his chest before he licks it up with a moan. “Gonna knot you and breed you. Fuck you full of pups so I get to do this all the time.”

“Shut up.” Tomura barely gets the words out but he can’t just not respond. “Shut up, shut up, shut up. Just fucking knot me, you idiot.”

He does and it’s enough of a stretch--god, how fucking big is this skinny bastard’s knot--that Tomura curls forward and bites the ever living shit out of his shoulder. No chance of getting to his scent gland--if it even still exists under the scar tissue--but he rends the fabric of that stupid jacket between his fangs until he hears it shred and keeps going.

Dabi finally unlatches, buries his forehead against Tomura’s chest, panting breaths making the skin slick with sweat as he rocks his hips through his orgasm. He can feel it inside, warmth that’s almost too hot pouring into him until he feels so full he never wants to move again. It’s enough to get him to wrap his legs around Dabi’s waist, arms back around his head, clinging like a limpet.

Fuck. Maybe the Omega’s in porn weren’t always faking it. This feels…

“Holy fuck, freak.” Dabi gives words to his thoughts, though he can barely understand him through the panting and the growl in his voice. “What was that?

“Shut up or I’ll kill you.”

Dabi, shockingly, does. Which makes Tomura think maybe he should fuck the zombie freak more often if this is the kind of obedience it gets him. Not to mention, it did feel good. Better than good. Fucking amazing. He feels better than he’s felt in years, like he’s floating as Dabi strokes an absent hand down his side and nuzzles into his chest.

“So,” he says after a while, Tomura cracking open one eye to look down at him. “This side think it’s gonna be a permanent thing? Every time you pop the meds?”

Oh, he’ll ensure it. He might even ask the doctor for something that makes it a little worse next time. Suffer a bit if it means he can do this again, get speared on Dabi’s knot as he sucks him dry.

But, instead of admitting it, Tomura snorts and closes his eyes, sinking back into the couch with a soft sigh.

“You fucking wish.”