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There is no way he could've anticipated this.
His palms itch. A grimace lines his lips but he doesn't let up on his explosions. The stupid bastard just won't go down.
"So persistent." The small villain chuckles, dodging yet another one of Katsuki's attacks. "It's a wonder I was put against you tonight. Just the person that I was looking for."
If Katsuki cared at all, he'd play into their game. Jumping over the strange waves of smoke they were throwing out, he sends a flurry of shots towards them, shouting in fury.
Vapour, the person Katsuki was currently fighting, had been on the wanted list for months. Several heroes had gone after them, but without fail, they all would be attacked with the quirk and immediately put under examination while the effects ran their course.
Katsuki was warned way ahead of time when he was called in to help, that the quirk could be dangerous and to be careful until they got an answer on what it did. He refused to acknowledge that, muttering that he knew what he was doing and flying into battle.
They've been at it for over ten minutes now, which in Katsuki's book is far too long for one measly extra to still be standing for. He usually has them either knocked out or pinned to the ground within five, but this fucker isn't as easy a target as others have been. This is what he gets for diving head first into it like he always does.
Now he's stuck on what to do. Backup had been called over three minutes ago (to his chagrin) by order of the police standing by. He knew they could only do so much as the villain's whole form was emanating the fucking stuff.
The patches on Katsuki's neck are beginning to come off as sweat leaks from the ends of his hair and forms in his juncture. Usually he'd pin them back in place and change them out at the agency but his hands are literal bombs right now, so he's left to sneer at his opponent.
Vapour must see this, as a grin slides its way onto their face. "You seem troubled, little hero." They jeer, placing their arms behind their head as if they're stretching. "Might need to get those fixed up."
"Not until you die, fucker."
Katsuki positions his body so he won't lose balance, forming a circle with one hand and holding the other with his palm out facing the villain, preparing an AP shot. He focuses all his attention to the middle of his hand, letting the sweat build up for the biggest explosion he's made in this fight.
But in doing this, he unintentionally gives Vapour an out.
The attack is so large that it makes the ground shake. It hits the wall where they are standing, and Katsuki grins wildly. He had done it again, successfully finishing a villain so he can put them behind bars.
But that smile disappears when the smoke from his explosion fades away and he's greeted with absolutely nothing. No collapsed body. No sounds of pain showing that he hit them.
Vapour was gone…
"You should always watch your surroundings when you set those off," A voice whispers against his ear, "someone could get hurt."
…or so he thought.
Katsuki doesn't think. Turning part way to hit them up close, he is thrown off by a hand grabbing at the nape of his neck, keeping him still as the smoke Vapour had been exuberating all night flies past his lips. Katsuki tries desperately not to breathe in but it is all for naught as it assaults his lungs, causing him to cough. It gives him no choice but to inhale to catch his breath, yet each one he takes makes more of it seep into his body. His eyes sting. His body shakes.
And then the villain laughs, stepping away from the blond. "Well my time is up here. I've done my job. It's time you get back to yours, hm?"
Katsuki bends over, feeling sick from the coughing fit. He can't even bring himself to glare as Vapour sends a two-fingered salute his way before running off.
First responders show up shortly once he leaves the demolished area, and paramedics are quick to wrangle him in, checking for any external injuries. This part is what Katsuki despises the most: the aftercare, the poking and prodding and cooing over his mild wounds he received.
After an extensive checkup, he is urged to go to the hospital right away to make sure nothing internal had been damaged by the smoke he inhaled. With a swipe of his hand to get the nurse's arms away from him, he stands up and waves her off. "Yeah, yeah. I'll do that." He consoles her, walking down the road before the paparazzi could show up.
He'll get checked out… eventually . Aside from the initial breathing problems, he feels fine, or as fine as one can be after that whole ordeal. All to do now is get out of his costume that is beginning to make him feel itchy.
It's a small trek to his agency building, strolling in without so much as a word said to the receptionist– who thankfully was a Beta– and the only one in tonight. His patches are held on by a metaphorical thread so he scoffs and rips them off, holding them in his gloved hand while he makes his way to the locker room. Damn his stupid sweat and his stupid glands.
The second the door shuts behind him, he's shucking off his costume and expelling the copious amounts of sweat down the sink from his gloves. Leaving them to air dry, Katsuki grabs a pair of casual clothes from his locker to wear so he can go home without the hassle of his costume. He believes it's best to take a shower where no one else can smell him after the fight, since his Alpha continued to be a little shit and was causing a fuss for no reason the entire way back. Maybe his rut was coming early or something. They'd always been irregular so it wouldn't surprise him if this one was the same.
Placing a new set of patches on, he snatches his bag and locks up for the night. He goes out the back way to avoid the slew of reporters that are outside his agency, grouped together like a flock of birds, awaiting their next big scoop. Thankfully it's an easy escape since it's so dark and he goes around the corner to grab his bike that he has parked in the parking garage.
Then he's on the ground, gasping for air.
Want…! His Alpha is screaming…something. His ears are ringing, fingers twitching where they've wrapped around his abdomen in pain. It feels like a round of cramps, all stored in his chest and stomach.
This is nothing like his pre-rut symptoms. The Alpha shouting isn't new, but the pain so excruciating it brings him to his knees? That sure is.
"Wh-What the fuck…" A harsh whisper passes his lips. "H-Hurts."
Damnit, why didn't he listen to that woman? Why did he have to be so damn negligent? 'I'lL dO tHaT' sure, Katsuki. Shoulda done it in the first place, you fucking–
"Well this is a surprise."
Katsuki freezes at the sound of a voice he knows all too well. The one that is now a permanent resident in his dreams, along with rough hands and sharp teeth that graze his neck–
His head snaps up; he is not prepared for this encounter in the slightest.
Vermillion eyes look down on his scrunched up form, "I mean, it was inevitable that you would end up on your knees in front of me, but I didn't expect it to happen this way."
There's a touch of amusement mixed in with the roughness. Katsuki hates him for it. "F-fuck off, Riot."
The night brings a shadow over the villain's huge build, the sign of the parking garage providing just enough light to see Riot's lips quirked into a smile.
Katsuki's body is betraying him. A flush paints his cheeks and the tips of his ears. The smell of Riot's natural Alpha musk hits him in the face, and what usually doesn't deter him sends a shudder down his spine. Why is my dick getting hard?! "I'll k-kill you."
"You can't even stand up, little hero." Riot drawls, cocking an eyebrow.
"Yes I can, asshole. I'll sh-sh–" he tries, he truly does, but his body refuses. The red headed villain comes closer, their distance dwindling. Katsuki has to bite the inside of his cheek to stop the needy noise that threatens to escape.
His erection presses uncomfortably in his slacks. Yeah, whatever that shit was wasn't something that only caused pain. It also made him embarrassingly horny. The quirk just so happened to make him aroused for the man he loathes; that's the only reason he can think of why the redhead is so appealing to him.
But that's not the worst of it. Something is leaking out of him… currently staining his boxers… and it's not coming from his dick.
He hears Riot's breath catch. Even through the shitty lighting, Katsuki watches his irises shift from the hue he's grown used to, to something else entirely. He's heard of people's eyes changing when they get turned on, but seeing Riot's transform and move into slits was… enticing.
Then two hands come underneath him, lifting with ease. A yelp comes flying out of Katsuki's mouth. "Put me down!! You fucking asshole–!"
"No."
Riot's voice drops, dripping pure arousal and possessiveness that makes Katsuki's already desperate body keen for more.
Despite all of that, he is not going to let this dickhead get the best of him no matter what this fucking quirk has done to him. Lifting his hands, he poises for an attack and tries to ignite an explosion–
But nothing happens.
Katsuki's face goes pale. Never in his life has he had something like this occur. Distinctly, he recalls back during his time at UA during the war when Aizawa had to remove a limb because of a quirk-canceling drug he was injected with. His mind begins to spiral. There's no way those were still out there somewhere, right? Did he get hit with one when he wasn't looking? Was he too late?
Or could this be a side effect of the quirk he was hit with? Possibly a temporary lapse of his powers whilst he was going through the current problem he was having?
That made more sense realistically. Curse this quirk for making his brain nothing but mush.
Where his palms usually radiate heat has dissipated, leaving the warmth to travel inside him instead, pulsating in places that it shouldn't be.
"Easy, Dynamight." Riot uses a tone that Katsuki has never heard. It's still the same cadence as before but holds a note of comfort in an effort to soothe the upset blond. "It's okay. I've got you." He croons, and in turn, Katsuki purrs.
Wait.
Purrs?
Alphas…don't purr. What…
"You smell like you're in heat." The redhead murmurs under his breath. Katsuki didn't even notice they had started moving or that he was holding onto the Alpha in a tight grip. "You got hit with a quirk, didn't you?"
Heat? Is that what this was? Did it change him into an Omega? Is that why his body is fighting him?
All of that and every other inquiry shortly leaves his mind as another wave attacks him, more…whatever it was… dripping out and staining his underwear.
Pink litters his cheeks, runs down his neck, and below the "v" of his tanktop. "Yeah, by one of your shitty friends."
"Unlikely. I don't have any." Riot scoffs. "I work alone."
Katsuki sighs but it comes out more breathless than he wants. "Then w-where the hell are you taking me, Shitty Alpha?"
"My den."
Katsuki had a den of his own, back at his place. Not all Alphas had one, as it was only made from those that went through any type of distress or needed to relax.
Hearing that Riot has one too passes his mind but quickly disperses as another hot flash whizzes through his core and he murmurs out an intentionally soft plea to hurry. For what, he's unsure. He lays his nose into the crevice of the other man's collarbone, inhaling petrichor and musk like it's oxygen. Like his being relies on it.
The walk there feels like it takes hours. Katsuki's body is buzzing with need, breath heavy on Riot's shoulder as he soaks in the comforting scent the villain is pumping out. He's never seen this side of the redhead before but he isn't complaining. He's treating him so delicately, like he could break at any point. Katsuki'd bitch and gripe about it but he's too busy whining, ass now covered in the liquid forming a puddle in his boxers and seeping through his pants.
When he's set down, his eyes quietly scan the walls surrounding him. It's an abandoned building, it looks like, one that would go unnoticed by any passersby that were in the vicinity.
One quick, hazy look over of the place shows how fucked Riot's living situation is. There's building debris that's been pushed into a pile, and a small, hardly working industrial lamp resting in the opposite corner from where Katsuki sits.
What he lays on is a crappy mattress layered with three different comforters and fluffy looking pillows, one of them stained red (most likely from Riot's dye job). His eyes pan up to a window wall that is partially exposed from many other blankets blacking out the view. He can see the city lights filtering through one of the slits. They don't seem far from where they just were, which settles Katsuki's nerves.
The sight of Riot's living arrangement makes Katsuki's belly twist unpleasantly. Where did he shower? Wash his clothes? Reality is more cruel to the redhead than he initially expected.
Though the rational side of Katsuki's mind was against all of this, he had no choice but to go with the other Alpha's actions. He's quirkless (only for the time being, he hopes) and can hardly stand up without his legs giving out. All he can do is pray that the Alpha places him here and leaves him be to get through this shitty predicament.
However, the second he puts him down, Riot is pacing back and forth in front of him, clenching and unclenching his fists. The room smells heavily of the redhead, the fabrics and blankets soaked in it. Katsuki's Alpha whimpers, and the blond cannot stop that part of him from taking over as he reaches out, whining around the villain's name.
Riot growls softly but Katsuki has a feeling it's more aimed towards himself rather than at him. Like he is trying to hold back from attacking Katsuki, and not in the way he usually does.
He sounds pathetic right now. His voice is up an octave, using a tone he would rather be caught dead showing anywhere but here, begging for the villain to get closer, to stop moving away from him and to touch him–
"Behave."
When an Alpha hears another Alpha's command, they react differently than Omegas or Betas would. Usually they would try to get past it and fight the other Alpha. But with the quirk in play, Katsuki submits in seconds, clenching his legs together and nodding his head. Why is he so submissive right now? What the fuck did this shitty quirk do to him?
He'll worry about it later. He's always been weak for the stupid redhead anyways– showing up wherever he may be, no matter if he was in the middle of working or not. Katsuki could take this meathead down easily, but has he?
Considering he's bowing down to the fucker, the answer is evident.
His dick could compare to a skyscraper right now, a patch of pre sitting where the zipper is, making a damp stain to match with the one that is plastered onto his ass cheeks. It's warm, he notes, and it has a distinct smell to it, akin to his natural Alphan scent but… sweeter. Like caramel or a freshly baked pie.
This is really fucking with him. Before all of this, Katsuki simply went through his ruts without any rhyme or reason behind his actions. It was clockwork: a well-used Fleshlight here, a ruined pillow there and then he was back to work. Boom. Done.
However this is an entirely different scenario. He feels like he's underwater, unable to fully control his movements. Though it's new and unfamiliar, the blond finds himself…almost enjoying it. It may be due to the quirk but right now his mind is blissfully blank, allowing his actions to do the talking.
The new patches on Katsuki's neck are ruined again. His scent glands are swollen, sending a wave of want into the room. His slacks are so uncomfortable. They itch at his legs and ass and suddenly it's too much fabric constricting him. He fidgets in place, fighting an internal battle until he says to hell with it, shuffling out of his clothes.
The pants are the first to go. Heat simmers down in his stomach, uncurling with each movement he makes in taking them off. His boxers are completely ruined, sopping wet with slick and precum that dripped from the tip of his dick.
It's so humiliating, being reduced to a mewling, flushed mess that has no control over his own body's reactions. While he thought that Riot would get on his case by going against his command, he's raptly watching it all unfold, a soft growl rolling from him.
Katsuki finally peels off the boxers, releasing his cock from the confines of it and allowing his ass to secrete the liquid freely. It puddles onto the mattress without anything holding it back, and Katsuki quickly sets to work jerking his weeping cock.
His hole winks openly at Riot, a free show for the villain that hasn't budged from where he's standing. Katsuki doesn't like that however, eyebrows knitting and dick twitching in his hand. "F-fucking… get over here, asshole. You brought me here, now help me–!"
"Bossy," Riot smirks, finally listening to the blond and waltzing over, bending down to get into his space. Katsuki leans back, eyes hooded. "Where did that spark go, hm?"
There isn't a need for an answer as Riot grabs two handfuls of Katsuki's ass, spreading him open to show off his wet hole. He licks his lips and hums in anticipation. "Stay just like this for me, sweet boy. I'll make you feel good, okay?"
Katsuki has heard people say how wonderful it feels to be eaten out, regardless of their secondary gender. His Alpha friend Tetsu, who is in a committed relationship with his Beta friend, Hanta, went on a tangent about it until Katsuki had to literally walk away because he started giving details.
His lack of sexual experience was obvious when anyone ever talked about theirs, and it made him mildly uncomfortable, only because he felt judged by his friends and he hated that the most.
Having the most wanted criminal's tongue flicking across his twitchy rim brings him to the realization that he really, really fucking likes it. Shaky moans run from his throat, twisting his palms into the itchy sheets above his head for leverage.
His cock bobs onto his abdomen, a small puddle of pre growing as Riot gets more intense with his motions, tongue and lips slurping on his hole like it's the last thing they'd ever do.
The slide of the wet muscle pressing into his ass has his eyes rolling into the back of his head, pushing into the thrusts. A few minutes pass and then a rough digit shoves in next to his tongue, driving into him.
One becomes two and then Riot's mouth is licking around the three fingers buried deep inside of the blond's ass. Tears bead up in the corners of Katsuki's eyes. His lower lip quivers, stomach flipping and causing him to arch his back. "Ah… Alpha!" It comes out as a strangled cry, more in pain than anything. "M-more. Give me more!"
His hole flutters around the intrusions, a physical sign that Katsuki's body isn't going to settle for the redhead's mouth and fingers for much longer. He needs something bigger. Harder.
"You're lucky I'm being so considerate tonight, little hero." Riot murmurs into a thigh, unbuckling his belt with one hand and fishing his dick out from the tops of his black pants.
Katsuki almost passes out at the sight of it. Red tipped and swollen, it twitches and drops pre from the head. The veins along this shaft are so visible that Katsuki is sure he could feel them on his tongue if he licked where they were. It bows under its own weight, creating the ideal angle for Riot to penetrate something/someone if he so wished.
Riot had unzipped and unbuttoned his pants so Katsuki could see his fat balls, too. His mouth fills with saliva and it takes every part of him to not put his lips around one. With Riot's huge stature, it was a given for him to be big everywhere else. Katsuki is not complaining, and his ass is absolutely okay with it, if the slick sinking into the mattress has anything to say about it.
"So pliant beneath me." Riot whispers, aiming his hard cock towards Katsuki's entrance. "Gonna stuff you full, sweetheart."
"Oh fuck, please. " Katsuki never, ever pleaded for anything. You'd catch him walking the streets naked before you'd hear him utter anything like that.
It's easy for him to do it now though. He's hungry for more of Riot's touch. Riot's hands. Riot's mouth. He needs it all.
"Fuck me." Katsuki chokes out. "Come on ."
Riot touches the tip of his cock to Katsuki's clenching hole, rubbing it gently along the sensitive rim. The blond makes a noise that says to get on with it and his back arches off the mattress when the tip breaches his ass.
The redhead doesn't wait to sink into Katsuki further. Inch by inch slides into him, letting him adjust to the size even though Riot wanted to plunge his whole cock inside. Sounds leave Katsuki that he will not admit he made later. Riot coos and kisses the tears clinging to the blond's eyelashes.
It doesn't take as long as they anticipated because of the slick the blond has rolling out of him. Once Riot bottoms out, his balls slap gently into Katsuki's ass cheeks, causing him to groan.
Katsuki is folded in half, knees close to his shoulders and feet in the air. Riot is hunched over him, hands on both sides of Katsuki's head with his face close to his. It's crazy, their circumstance; Riot is insane, a man to not be reckoned with, and yet he touches Katsuki so lightly, being just a tad forceful but not overly.
The blond's eyelashes flutter. This Alpha, this man, someone Katsuki had been rivals with for years, took care of him like they'd done this countless times before. Lifting his hands and digging his fingertips into Riot's shoulders, Katsuki searches the villain's face, sending him a message that he was alright now. That he wants this. Thankfully Riot understands from the expression alone, and then he's moving.
It's not slow or methodical. It's not careful. Riot is feral with his motions, fucking into Katsuki earnestly. Soft grunts and the occasional chuff escape him but he's otherwise quiet.
Meanwhile Katsuki could wake an entire city up from how loud he's being. Riot is so fucking big, filling him up perfectly and hitting a spot Katsuki will forever aim to hit when he masturbates in the future. His hands grab at the sheets in desperation, eyes unfocused and mouth dry.
He popped a knot a long time ago but it's useless, bobbing between his legs like a decoration. In this case that's all it is and yet Katsuki pays no mind to it. His thoughts are all jumbled by Riot's huge Alpha cock.
"Dreamt of doing this for years." It's the first thing Riot has said in the last several minutes. It's breathy, broken sentences that Katsuki can piece together with the last remaining brain cell that's working. "Fucking into… knotting you and… till you were bursting…"
"R-Riot–!" Katsuki whines, reaching a hand up to grasp a handful of the villain's long red hair. "Please, please !!"
He doesn't know what he's begging for, but his body is keening for a release. Suddenly, his Alpha roars, saying something Katsuki is least expecting.
Need knot. Need knot. NEED KNOT.
"That's it, Katsuki. You're doing so good for me." It's the first time the villain has stated his name and it makes his stomach whirl in excitement. "Cum on my cock. Make a mess, sweet boy."
Katsuki reaches down with one hand and strokes his cock in time with the redhead's thrusts, "God, fuck. S-So much. Don't stop, Riot–"
The villain lowers his face, still pounding into the blond. " Eijirou . It's Eijirou." He corrects. Katsuki feels goosebumps rise on his body. "Say it. Say my name, Katsuki. Say my name while I knot you."
Eijirou. It is perfect for him. For the Alpha that plagued Katsuki's every waking thought. For the villain that has escaped from many fights because Katsuki allowed it.
It throws Katsuki over the edge and with a final arch and his abdomen tightening, he yells out, "Eijirou!!"
The villain's hardening ripples down his arms and along his palms, nicking Katsuki's flesh. A bulge that was undeniably Riot's knot passes his stretched rim, locking them together. Cum spills into him, so hot and thick it makes Katsuki dizzy.
Pieces of long red hair fall into the side of his face and a weight pushes by his head. Katsuki faintly hears the sound of something ripping. Albeit untethered from reality, he tilts his head only to hold back a moan threatening to rip itself from his throat.
Riot had dug his fangs into a pillow, tearing straight through it. His eyes glow in the faint light that is being cast from the corner of the room. Soft groans fall from the redhead, jaw clenched around the fabric for several seconds as he releases another load into Katsuki.
The intensity of the orgasm and the pressure of Riot's knot and cum filling him sends Katsuki's body into a temporary shock, and his eyes roll back, making him fall unconscious.
The next several hours were a blur. Riot was right in assuming that the quirk would go for a while, because as soon as Katsuki woke up, slick was collecting around Riot's cock that was still buried inside of him. He honestly thought that the hero would try to get out of it, or to attack him. He isn't ready to see Katsuki gaze up at him and grab his steadily growing cock by the balls to manually make him thrust inside again.
Exhaustion grew in Riot's bones as time went on. He would fall asleep for a few seconds and wake up from Katsuki riding his cock like he was nothing but a toy until he inevitably knotted the blond again. That was fun.
It'd barely been two hours since Riot finally heard the hero pass out, covered in a mixture of their fluids, both leaking out of him and painting his tummy.
Now the sun is rising, signaling that a new day is starting. The night had cooled his "home", but the sheets covering the two of them were enough to keep them warm.
The redhead's room reeks of sex and sweat. The small opening from the curtains lets the sunlight come in, making Katsuki's pale skin and light hair so much brighter. Riot had placed two shitty off brand scent patches onto his glands before knocking out to at least cover the already overwhelming smell of caramel that flooded the room. If he didn't, he's sure that a pillow wouldn't stop his need to claim Katsuki.
He's shocked he was able to pull himself away from Katsuki before he bit him. The Alpha just looked so delectable and pretty begging for his cock, and that same thought extends to now, watching the blond snore.
Katsuki is ethereal. Riot lets a small smile light his lips. Years he had been pining after this explosive hero, someone that he gravitated towards the second he saw him in action, attacking some nameless villain he can't recall who was trying to rob a store. Since then he had made it his mission to be the one in Katsuki's line of sight. There was no way he was letting someone like him get away.
And now he's in his bed, not necessarily in the way he was wanting but he'll take what he can get.
He knows once Katsuki wakes, he'll curse up a storm and limp out of his place, promising to beat his ass next time he sees him. For now Riot turns on his side, grabbing his phone and scrolling to the most recent news report he is sure the press made on Katsuki's latest fight with the info they could scrounge up.
He'll need to know the extra that dared to touch what's his after all, that way they can sit and have a nice, long chat.