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Part 20 of BakuDeku Smutfest 2023
Collections:
Gays Writing Gays, Maybe I Just Like Magic(Completed Favs), The Best of the BNHA (mostly BKDK), It’s Smut Your Honor, BKDK: dont let me get STARTED on how good this ISSS!!! (E only), BKDK fics that sent my soul, obscure bkdkbk
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Published:
2023-06-04
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2023-06-26
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104,913
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16/16
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361
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Unorthodox Paradox Syndrome

Chapter 16: Full Circle Again and Again

Notes:

8k words, 4.1k of smut, enjoy my fellow degenerates 💜

(See the end of the chapter for more notes.)

Chapter Text

One thing Katsuki almost never does is sleep through his alarms. Another thing he almost never does is wake up with a splitting headache, because the last time he had a hangover it severely fucked with his day. So it super pisses him off to rouse late on a goddamn Wednesday, suffering a headache from hell, only to squint at his phone and see that Jeanist has tried to call seven. Fucking. Times.

Fuck.

He’s so pissed that he doesn’t even try to recall why this is happening. Just scrambles out of bed, curses frenetically, and calls Jeanist back while he dresses. No time to do much more than brush his teeth and get out the door.

Somehow, he does get the feeling it’s Izuku’s fault.

***

Though more an obligation than a gift, the quirk time commission helps weave a tapestry to keep the timelines intact. It’s part of their job, and despite their inherent flaws, they take their brand of heroism as seriously as anyone else.

***

Days off for heroes are their own blessings. Even a workaholic like Izuku recognizes the need for spare time. How else will chores get done? How else will he find time to catch up with his friends? And how else would he ever spend any (even if it’s minute) quality time with Kacchan?

So, yes, he does actually treasure his days off. It just sucks that on this one, he wakes up with a splitting headache. His skull throbs so horribly that he can only focus on stumbling out of bed, fumbling around for a glass of water in the kitchen, and using bleary eyes to locate Bufferin A. He eventually finds it in the bathroom medicine cabinet and takes double the dose.

(Shh. Don’t tell anyone.)

“What in the world,” he mumbles to himself. He doesn’t remember drinking last night… and he hasn’t been out to a get-together with his friends in at least a few weeks. Uh. Maybe a couple months? Time suddenly seems very fuzzy.

After crawling back under the covers, Izuku tosses and turns for two solid hours. That’s as long as it takes for the pain to finally subside into something manageable. By then, it’s almost noon, and his stomach protests the lack of nutrition.

After checking his phone—some of the messages are puzzling, like Uraraka’s, Haven’t seen you on patrol, are you okay?—but easily replied to with, Just been assigned to different areas for a bit, should see you tomorrow! Little things like that.

Still, they strike him as… odd. Even if he can’t quite place why.

Izuku makes his way to the kitchen and pauses. Frowns at the coffee pot. He doesn’t recall using it recently, yet it’s about a quarter full. When…?

A flicker of movement outside his window is his only warning. Izuku catapults into the air the same moment someone smashes through the window and half of the wall. One For All is already activated, lighting green along his skin, when a resounding, BOOM! in the distance lets him know that this is not about to end well.

The person—a villain, by the looks of his costume—clambers to his feet. Claws his hands and screams, “Don’t mess with me!”

Get out of that house, asshole!

Dynamight launches in, snagging the villain by his cape and throwing him out again. Before Izuku can yell a warning, the villain halts in midair and zooms right back at them, unleashing tiny white balls of electricity.

“Deku, move!” bellows Dynamight.

He trusts Kacchan. So of course he gets out of the way before the balls erupt. His apartment doesn’t survive the expulsion of electricity, nor the fire that catches after.

And Izuku definitely doesn’t get his security deposit back.

***

The one thing the quirk time commission can’t affect, no matter how hard they try, is the concept of “muscle memory.” That in itself leaves new paradoxes for the universe to resolve.

***

Sifting through his burnt things in a suddenly open-concept apartment is not how Izuku thought to spend his weekend, but, well, things happen, and both his and Katsuki’s bosses seem insistent that they actually take the weekend off. No idea what that’s about, but.

Here they are.

For the life of him, Izuku can’t figure out why Kacchan is here. He stomps around grumpily, tossing burned things into trash bags, bitching and complaining about the hassle and how he’d rather be on patrol.

Yet he stays. He stays, and for some reason, it strikes Izuku as… odd. He keeps seeing, in his mind’s eye, a faint overlaid vision of Katsuki clicking his tongue and walking out. The longer they sift through Izuku’s belongings, however, the fainter it gets, until Izuku suddenly can’t remember what he was thinking about anymore.

He’s managed to salvage a few scant things (mostly some clothes and a few of his precious All Might memorabilia, thank goodness) by the time his phone rings. Izuku digs it out of his pocket, covered in soot and grime, and answers.

“Hello?”

“Izuku!” He flinches at the sudden wail of his mother. “I just heard—how did this happen? Where have you been sleeping? Are you okay? What—”

“Mom,” he interrupts, desperate to calm her. Izuku drags a dirty hand through his hair. “I’m okay, honest. These things happen.”

They chat for a brief while, mostly Izuku catching her up on the details of the villain attack. Once she’s calmed down enough to breathe without asking how he’s doing, Izuku manages to stutter out that the government has put him up in a hotel for the past few days. Though, he knows, that concession won’t be around much longer. He needs a backup plan.

Izuku slinks into the hallway to avoid the nasty breeze from the open wall, sliding down onto his butt while his mother keeps talking. Then:

“Where will you stay now?”

“Eh?” He blinks, then closes his eyes. “Ah… I mean, I’m sure I can… um…”

Inko presses. “Izuku, sweetheart, you can always move home. Just until you get back on your feet.”

He opens his mouth to accept, mostly on reflex, but hesitates. Some niggling thing in the back of his mind tells him to say no, and it… it doesn’t make sense? It’s his mom.

“I—hey!”

Katsuki snatches the phone from Izuku’s hand, pressing it to his ear. “Auntie, hi.” He pauses, grimacing. “Uh huh. Yeah, I’m helping him out—of course! Ugh, no, don’t tell the damn hag!”

Izuku clambers to his feet. His heart is pounding funny. Like it can’t expand properly, so it thumps sideways, back and forth in his chest like a rattle.

Then, to his utter shock, Katsuki says, “Nah, he’s staying with me.”

Izuku’s eyes nearly bug out of his head. Katsuki shoots him a warning glare before turning on his heel and stepping away. “Uh huh. Fuck, it ain’t a big deal. I’m sure he’ll have a blast. Like we’re in the dorms or somethin’.” Despite his heavy sarcasm, the red tinging the tips of his ears is unmistakable.

It’s like Izuku’s stepped into another world. What is this? How is this happening?

Why did Kacchan decide… this?

Abruptly, Katsuki says, “Auntie, the disposal truck’s here, we gotta go. Yeah. Bye.” He hangs up and tosses the phone over his shoulder. Izuku fumbles to catch it.

Finally finding his words, Izuku says, “There’s no disposal truck.”

“No shit, asshole. It’s called a lie.” Katsuki grabs a full garbage bag and tosses it by the door. Still not looking him in the eye.

Izuku is still hesitant. He should say no. All the old arguments well up inside him, toward his throat. I can’t put you out like that, Kacchan. It’s okay. It’s just until I can get a new place. I’ll stay with Mom, or ask Todoroki…

And yet, he can’t bring himself to voice it. He searches deep inside, trying to find that hesitance. That thing that’s always kept him at least five emotional feet from Kacchan.

It’s not there. Just broken pieces turning to dust in the wind.

Once Izuku salvages what he can—no more than a single tote—he meets Katsuki by the front door. Even with the wall blown open, they still need to use the hallway. Management will definitely be after Izuku if any more quirk damage is done.

Katsuki swipes a sweaty hand over his forehead, smearing soot. Gives Izuku a flat look. “You need a shower.”

“So do you.”

“Asshole.”

Izuku grins.

Somehow, they make it to Katsuki’s apartment without another word of discussion over the issue. It just falls seamlessly into place.

***

Izuku’s noticed a couple new strange things here and there. He wears long sleeves despite the warming weather, and ensures his neck and shoulders are suitably covered for the next week. At least until the weird bite mark starts to fade.

Somehow, it makes him sad to see it go.

***

In typical Katsuki fashion, he doesn’t defer to guests and takes his own shower first. Izuku is forced to wait in the kitchen (“So you don’t ruin my shit!”) until he returns, damp but clean and dressed. Katsuki ruffles his hair with a towel and mutters, “Go shower, nerd. You fuckin’ reek.”

Izuku bites down the horrible urge to tell Katsuki how good he smells as he passes him. Even so, he can’t help thinking about it… or about the bandage that he carefully peels off before hopping into the shower. He stares at his wrist while the water soaks his hair.

It’s a tattoo, obviously. But… Izuku doesn’t have tattoos. And he doesn’t understand why he’d have this, of all things.

He washes himself down carefully, until the water runs clear. Then he stands still as the water begins to cool, gently tracing the pad of his finger over the sensitive, peeling skin of the tattoo. A bit of orange gently flakes off. He wonders if that’s okay.

The door to the bathroom bangs open. Izuku yelps.

“What the fuck, nerd! Just because I said you can stay here doesn’t mean you can quadruple my water bill,” yells Katsuki.

Izuku fumbles to turn off the water. “S-sorry.”

“Fuck. Asshole. Hurry up, I gotta piss.”

Izuku looks down at his wrist again. Swallows. “Um… sure, just step out and give me a sec—”

The sliding glass door slams open. Izuku gasps and then his face is full of black towel, rough hands guiding it over his cheeks. “Get. Out. Nerd.

Izuku splutters, instinctively raising his hands to fend him off. “K-Kacchan—pbbt, stoppit! Ow, that’s my eye!”

But then the hands go still. Vanish. Grasp his arm and yank.

Izuku’s stomach plummets through the floor. He clutches the towel over his head, slowly lowering it. Scared of what he’ll see.

Katsuki has a firm hold of his left arm, the inner part of his wrist facing the ceiling. Those calculating, critical red eyes narrow on the tattoo. It’s simple, nothing worth writing home about, all done in dark orange ink… nothing remarkable, except for the fact it’s two bold kanji letters spelling out Katsuki.

This is it. Izuku is about to die over something he has no idea even got there.

Katsuki’s nails dig into his skin. His voice is hoarse and angry. “What the fuck?”

Izuku swallows. Hard. How can he say anything? There’s no defense. Just… Katsuki’s name. Tattooed. On. His. Wrist.

A deep, sharp inhale expands Katsuki’s chest. Then, with a harsh yank, he pulls Izuku out of the shower. Pushes him toward the bedroom with a snarl.

“Get dressed.”

Izuku stumbles out, legs shaking. The door slams shut.

Oh god. Now what?

He should flee the country, for sure. But, uh. First he needs clothes. And it looks like Katsuki’s laid out some of his own; a pair of shorts that are a little too tight around the hips and a loose black shirt that reads, Menace.

Izuku barely has his head through the neckhole when the door bangs open again. He makes a loud eep and stumbles back, his knee striking the frame of Katsuki’s bed before he topples onto the mattress. Katsuki advances toward him, and Izuku hates himself for how entranced he is: the spiky halo of golden hair, the demonic red eyes narrowed in determination, how his strides are quick and sure.

A quirk-callused hand grabs his arm again. Izuku starts to jerk back, but Katsuki barks, “Hold still!” and some part of him can’t help but obey.

Admittedly, he doesn’t expect Katsuki to carefully apply a transparent bandage over it.

“Uh,” says Izuku intelligently.

Gruffly, Katsuki says, “Planned on gettin’ my own ink soon. This stuff’s supposed to be like protective skin. Best shit they have on the market.”

Izuku blinks rapidly. And then does it several more times. “Erm… thank you?”

“Shut up.”

Yeah, okay. He can do that.

Izuku keeps waiting for Katsuki to storm off, but he doesn’t. In fact, he grips Izuku’s arm even tighter. It’d hurt if, you know, Izuku wasn’t one of the strongest humans alive.

Slowly, so slowly, Katsuki’s eyes raise to meet his.

Thud-thud-thud-thud. Izuku’s heart is screaming.

“So,” says Katsuki, in that fake-neutral tone that indicates he’s hiding a much stronger, powerfully dangerous emotion. “What’s this for?”

Izuku chokes on his own words for a moment. “Uh… if… if I said I didn’t know… would you believe me?”

“No.” Katsuki’s answer is flat; immediate. Then his free hand comes up to yank the shirt Izuku barely got on back off. He ignores Izuku’s protests, pressing two fingers hard into his trapezius. The bite mark is healing nicely, though the indents are still visible. Gruffly, Katsuki says, “What about this?”

In a faint whisper, Izuku says, “I don’t know.”

“Hm.”

His pulse is going wild, a harsh, rapid drum solo in his ears. Izuku swallows and swallows and swallows as Katsuki presses into the healing bruise, then gentles his touch, and then pushes down again. His jaw is set, his eyes squinting in pure concentration. Like he’s studying Izuku.

It’s… kind of (really, super) hot.

After a very long, tense silence, Katsuki looks him in the eye again. Izuku damn near has a heart attack.

Steady, cold, Katsuki says, “I’m gonna do somethin’. If you hate it, punch me in the face.”

“Huh? Why would I—” Izuku cuts himself off with a strangled gasp. Katsuki… he’s…

whoa

his face

is buried in Izuku’s neck, teeth clamping down hard right where the mark is. Izuku whimpers, feels himself melting, his cock stirring with rapid interest. Part of him is mortified, but mostly his hormone brain is screaming for joy and demanding that he get more, more. Izuku doesn’t think, just reacts, clutching Katsuki’s shoulders and whimpering, “Harder,” and Katsuki bites down harder, so hard, it hurts and feels so good…

The pain eases, then throbs horribly, followed by a gentle, sweet, soft press of lips, right under his ear and

Izuku

melts

into a puddle of wow oh my god this is a dream whoa.

He barely gets his eyes open when he smells mint, like toothpaste, and then a searing hot mouth covers his. Izuku responds with eager, looping his arms around Katsuki’s neck, pulling him back and down onto the bed. Meeting his tongue with savage need and just allowing his brain to become overcooked, mushy soup.

It’s like coming home.

There’s nothing rough about it, just heat and slow, careful exploration. Wet and comforting. Like falling into a bubble bath after a long flight home. Especially when Katsuki draws back just enough to lick across his lips, gathering up a little saliva there, and holy good god that’s hot. A rough hand cradles his face, large thumb brushing across his cheek like he’s trying to smear Izuku’s freckles.

Izuku whimpers, and the sound jolts them. Katsuki’s eyes widen. Izuku goes absolutely still.

Neither move to pull away. Just that intense closeness, confusion, and… still… comfort. Somehow.

“Izuku,” rasps Katsuki. “That’s… I…”

“I like you,” blurts Izuku.

Katsuki hesitates. Then goes red. Groans and buries his face in Izuku’s neck, over the throbbing bite mark, so Izuku has to swallow a desperate keen.

Breathing unsteadily, Izuku manages to stammer, “Actually, I, um—”

“Shut up.”

Fear crackles through him. Izuku can feel his body going brittle, ready to fall to pieces.

Katsuki lifts his head, eyes shiny, ears so bright that they’re like Christmas lights. He speaks hoarsely. “Fuck you. I love you.”

Oh

wow

That’s…

Izuku slowly reaches up. Traces a finger over the shell of Katsuki’s ear, startled when he encounters a little piercing up there. He tucks his hair back, admiring the silver bar for a few moments. Toying with the skin around it, which is fleshy and fully healed.

He feels brave again. (Again?)

“Um, Kacchan?”

“Hn?”

Izuku allows that hand to trail down his face. Over the faint scars after their battle with All For One. Down his neck, dipping slightly under the collar of his shirt, while Katsuki visibly tries and fails to suppress a shiver. It feels like Izuku’s heart is in his throat when he says, “Can I, ah, love you back? Is that… okay?”

Something dark passes over Katsuki’s eyes. His breaths grow harsh and shallow.

Before Izuku can take it back or apologize, Katsuki claims his mouth.

This isn’t gentle or sweet. It’s brutal. Like Katsuki is trying to devour him with teeth and tongue. Izuku can barely breathe under the onslaught and that’s okay. It’s perfect.

Knotting his fingers in blond hair, Izuku moans into his mouth. Katsuki shoves him back to the bed, cautious of his healing tattoo, still pinning both wrists above his head as he kisses him. Licks across his teeth, his lips, down the side of his face, his ear, back up, whispering Izuku’s name before they’re kissing again. Izuku groans and arches up into him and whoa.

Katsuki’s, uh. Hard.

Like.

Ragingly.

Izuku’s lungs nearly collapse when Katsuki gasps. Then those hips are grinding down into his and oh. It’s heat and wonderful and sends beautiful little zaps through every nerve until Izuku feels like he’s floating. All he can do is wrap his legs around Katsuki’s waist and rut up and yeah, yes, just like this…

He almost jolts out of his skin when Katsuki tears back, pushing himself up on his hands. Gravelly, desperate, he says, “Izuku, wait.”

Izuku freezes. His heart bobs between his stomach and his throat.

Katsuki looks lost for a moment. Like he hasn’t found all the right words yet. Then, tentatively, he says, “Have you… I mean… shit.” He exhales shakily. Izuku’s heart goes out to him, realizing he’s never seen Kacchan quite this vulnerable. “I… are you a…”

Oh.

Izuku bites his lip. “Um… if you’re trying to ask if I’ve had sex, then… yes.”

He watches Katsuki battle something in his head in real time. His lower lip sucks between his teeth, a particularly sharp canine worrying at the flesh.

It doesn’t change how I feel, Kacchan.

Izuku reaches up, brushing hair behind Katsuki’s ear. “Kacchan… I love you. I’ve… always. Always loved you.”

Still, Katsuki looks unsure. “I’m… hell. Izuku, I like it… rough. Like being rough. And I don’t…” He frowns. “I’ve only bottomed once. And it sucked.”

Somehow, Izuku feels like he’s had this conversation before, even though the information is shockingly new. He thumbs down the tendon in Katsuki’s neck, breaths damp. “You don’t have to. I’m good either way.”

It’s like something cracks inside of Katsuki. He groans and flops onto Izuku with his entire weight. Izuku squawks rather unattractively, but then—

“I wanna… for you.”

Oh. God. There’s so much to process that Izuku is beginning to feel overwhelmed.

He clears his throat. “Um… I’d like that. But…” Feeling abruptly shy, he averts his gaze and trails his thumb down to Katsuki’s protruding collar bone. “This time… I’m comfortable bottoming. Uh. Because… I just wanna focus on you.”

Those powerful, quirk-strengthened arms tighten around him. Katsuki sighs harshly into his ear. Nuzzles into him. Presses a kiss there, then into his curls. It feels… tender. Something that’s both comforting and surprising. Those acerbic lips fumble their way back to Izuku’s mouth, little kisses at first, chaste.

Katsuki breathes, “I can be soft…”

“No.” For Izuku, it isn’t even a question. He glides his hands down Katsuki’s sides, then into his shirt, dragging his nails up his back. Katsuki hisses. “Be mean. Or rough. Whatever Kacchan is. I want you.

A low snarl answers. Katsuki presses their foreheads together, rough and bruising, almost tight. His eyes flash with equal parts warning and desire.

“Then you’re getting me, nerd.”

Katsuki’s hands slip into his hair, turning his head just so before he seals their mouths together. Izuku sighs, blissful. Paws up Katsuki’s back, down his arms. Tracing muscle he’s seen but almost never actually touched, not with his bare hands, and certainly not like this. As though inspired, Katsuki tilts his head back even further, brushing his tongue over the seam of Izuku’s lips. Plunging in, hot and thieving and determined, like he can scoop out Izuku’s soul this way.

Izuku immediately decides that Katsuki can have it.

Of course, Katsuki’s hands are far from still. Patting down Izuku’s chest, digging blunt nails into his sides until Izuku lets out a chortling squeak. Smirking before biting Izuku’s lower lip, encouraging his mouth open again, and wow, holy crap, Katsuki knows just where to put his hands. Thumbing Izuku’s nipples, stroking down his sides before hooking into his borrowed shorts.

In a strange, breathy voice, Katsuki says, “Changed my mind. Don’t fuckin’ wear my clothes.”

Izuku has no chance to retort before Katsuki yanks them off, fully exposing him. A slew of curses fall from Kacchan’s mouth. “What the fuck, Izuku… you’ve been packin’ how goddamn long? Jesus. Shit.” He roughly grabs Izuku’s shoulders and slams him back to the mattress, eyes aflame. “Hold still.”

“Kaccha—hah!” His attempt to speak melts into a short burst of air. Izuku squirms as Katsuki pins his hips with both hands, mouthing wetly down his chest. His tongue doesn’t miss a single scar along the way, practically worshiping Izuku. It unfurls something within and makes him set sail.

Once Katsuki’s mouth tightens around his cock, Izuku is done for. Any slight chance of doubt, of thinking twice, is immediately obliterated. He rocks himself up onto his elbows, gasping for breath, in awe of the way Katsuki works his way down with single-minded determination. His lips stretch around Izuku’s girth. When he draws back up, it’s just to inhale before sliding further down this time. And again, and again, until he’s damn near able to take him to the hilt.

Screw a dream. This is his own personal heaven.

Izuku reaches down and slips his fingers across the Katsuki’s forehead. The blond flinches but doesn’t pull back, eyes raising to look at Izuku with fierce pride. His heart swells in response.

“Kacchan,” he says shakily, “you’re beautiful.”

A low, muffled growl answers him, and then Katsuki swallows the rest of him down, straight to the back of his throat.

Izuku moans, his head falling to his chest. Eyes fluttering as the pleasure of wet heat thrums over him. The absolutely sinful way Katsuki bobs his head makes his dick throb. It’s the most incredible thing Izuku’s ever seen, and he wants to burn it deep into his brain.

Every guilty fantasy pulses to life right here. Izuku could float off the bed if he wasn’t so intent on watching Katsuki for as long as he can handle it. He wants to grasp Katsuki’s hair and fuck into his mouth, but can’t, won’t, because they haven’t negotiated those kinds of things yet, and it’s not something a good partner can just spring on a whim. So he commits himself to savoring every delicious drop Katsuki will give him.

Then Katsuki wraps his hand around the base, and Izuku whimpers. Chews the inside of his lip, palms at his face as Kacchan begins to suck and drool with such intensity that it pulls that hot, tense coil in his gut further downward, tighter, burning bright and threatening to char his insides.

He’d absolutely burn for Katsuki. No questions asked.

Just when he sucks in a breath to warn Katsuki that he’s close, the other man pops off without a word. Panting, swiping his mouth with the back of his hand, running his tongue behind his lips. Izuku can’t help fumbling for him, dragging him up to kiss him and feel the indents where he used his lips to cover his teeth.

“Kacchan,” he gasps into his mouth. “Fuck me.”

“Holy shit,” whispers Katsuki. That’s all Izuku gets before he’s thrown back down, flipped over to his stomach. Katsuki yanks him up by the hips, draping himself over him. Izuku isn’t afraid when he feels Katsuki’s cock, just a little nervous, but then Kacchan slides over him, simulating a fuck, and the nerves melt like sugar on his tongue. He whines and arches back. It feels surprisingly good; not enough to come from, obviously, but it kindles a warmth in his belly that helps him feel desirable and wanted.

Katsuki groans into his neck, peeling himself off and grabbing a handful of Izuku’s ass. “Fuck, and here I thought you were innocent,” he mutters, seemingly more to himself than anything. “Fuckin’ hell, Izuku.” His nails bite down, earning a delighted noise from deep in Izuku’s throat. “Should’ve known, this ass is made for a goddamn whore. Jesus, baby, look at you.”

The pet name damn near fries whatever’s left of Izuku’s working brain. He grinds back into Katsuki, hissing as he digs his nails in again. “Y-yeah…? What else… am I? Kacchan?”

Cursing profusely, Katsuki bends down and bites his shoulder. Izuku lets out a mewl of appreciation. “Apparently a goddamn slut magician,” says Katsuki into his neck. “Fuckin’... how the fuck, this mark… my mouth fits perfectly. Who the hell gave you the right to be made for me?”

Izuku’s dick is throbbing. “Kacchan, please…”

A harsh, resounding slap to his ass makes him choke. “Shut up. Fuck.” Katsuki smacks his ass again, around the same spot, and it feels like a whip burn albeit wider. “Trying to appreciate you, goddamn whore, shut the fuck up.”

God, yes, this is perfect. Izuku rocks back against him, pressing into the hot hand clutching his abraded skin. Katsuki utters another string of swears before pulling back. Panicking, Izuku almost turns on his back to see where he’s going, stayed only by Kacchan’s snarled, “Hold still.” And uh. Yeah. That’s… that’s fair.

Katsuki returns, pressing something cool against Izuku’s calf. Sharp bites down his back turn Izuku back into something more puddle than man, wriggling and moaning as Katsuki sucks patches of skin, hard, enough for Izuku to feel the blood pool just beneath.

Yes, Kacchan, please, mark me up, show everyone I’m yours, please, Kacchan.

He hears the snapping of a plastic cap. Izuku shudders in anticipation, yelps when cold, slick fingers circle around his hole.

“Fuck, baby,” mutters Katsuki. He sounds a little distant, and a quick glance over Izuku’s shoulder shows his eyes are a little glazed, like a man who’s been starving has just been presented with a full course meal elegantly laid out. “You know m’gonna fuck you up…”

Izuku nods, dropping his head to his arms. “Do it,” he begs. “Please, Kacchan.” His balls ache from waiting—and it’s so unfair, because Katsuki seems to know, his wet fingers sliding down to trace over them. A plaintive whine slips out of Izuku’s throat.

“Shh, shh,” coaxes Katsuki. He offsets the gentle sounds with a sharp bite to Izuku’s ass, making him cry out. “Only thing I wanna hear from you is crying, got that?”

Oh… god, please.

Izuku struggles to stay still, wanting so badly to just lurch back and force Katsuki’s fingers inside. Though it’s been several months since he last had sex, somehow he feels ready, like he’s only gone a few days. It’s crazy the effect Katsuki has on him.

A dark chuckle sounds against his spine. Katsuki’s teeth graze one of the bruises he sucked in. “S’pretty damn telling that you listen best when you’re about to be filled, ain’t it?”

Yes, yes, it absolutely is, so please.

After what feels like hours of torture, just those nimble fingers circling his hole, Izuku feels like he might pop a vein in his forehead. He sucks in a breath to complain—and then Katsuki gives him a taste. Just the tip of one finger, barely anything, yet it’s enough for Izuku to grind out a long, needy moan.

“Stupid nerd,” breathes Katsuki. His voice floods with confidence and sin. It’s going to split Izuku in half long before his cock does. “Barely even touching you.”

Izuku swallows the urge to scream, Because you’re torturing me!

“What a patient little whore,” says Katsuki in a condescending tone that has Izuku biting his own tongue. “C’mon, show me what you want.”

Is it a trap? Izuku finds he doesn’t care, immediately rolling his hips back, pressing more of that single finger in. It’s not enough, it barely scratches that itch.

Katsuki laughs. “Desperate fucker. Look at you, trying to get off on one finger. You ain’t got a dick that thick and just need one finger to come, do you?” When Izuku just grits his teeth, Katsuki grabs him by the hair and yanks his head back, exposing Izuku’s throat. A bead of sweat trickles down from his jaw. He can barely see the hungry sneer Katsuki roams over him. “Do you?

Izuku swallows. Tries to, at least. It’s difficult with his neck at this angle. He manages to choke out, “Do I what?” God, he can barely concentrate. All his attention is on Katsuki’s hands, the way his knees pin Izuku’s calves to the mattress. Anywhere they’re touching.

With a harsh yank, Katsuki hisses, “Do you expect me to believe you can get off with just one. Fuckin’. Finger? Slut?

A broken moan bubbles out of Izuku’s lips. “N-no…”

“Didn’t think so.” Katsuki roughly shoves his head back down. “Fuckin’ take what I decide to give you, goddamn needy bitch.”

Oh, this is heaven. Like a lifetime of being taunted by Kacchan is finally coming full circle.

Izuku yelps when Katsuki adds a second finger, more out of surprise than anything else. The stretch is wonderful. Still not nearly what he needs, but so, so much better than what he’s been given so far. He rolls his forehead against the mattress, whimpering, “Thank you…”

A harsh bite to the back of his neck, and Katsuki begins stroking inside, coating him with lube. “Such a polite whore,” he murmurs, voice all soft and gentle compared to just moments ago. It’s giving Izuku’s dick whiplash and it’s awesome. He pulses, throbs needily in response. “That’s it, baby. Good job. This enough for you?”

“No.” Izuku bites the sheets when Katsuki barely misses his prostate. “No! S’not enough!”

“Greedy bastard,” mutters Katsuki. The pads of his fingers brush over Izuku’s prostate, and oh, it’s like fireworks up his spine, crackling and lighting off beautiful patterns in the back of his skull. He melts into it, drooling on the sheets, uncaring of how he must look so long as Katsuki just does it again.

Of course, Kacchan has never been simple or straightforward; not right away, at least. He snickers, another taunt, and lightly grazes the spot again before purposefully fucking his fingers in and purposefully missing. It’s so close and mean that Izuku has to bite his arm to muffle the curses he wants to fling out.

“Aww, baby wants stimulation.” Katsuki rakes dry nails down Izuku’s chest, forcing a pain-pleasure cry from his throat. “How’s this?”

Izuku’s dick is full and heavy and painful. “Kacchan, please!

“Please what, asshole?”

Please.” Izuku gasps at the jab against his prostate, bordering on painful but mostly just exploding heat in his lower belly. He’s close just from the edging alone. “P-please get inside me!”

“I am inside you.”

Izuku grinds his teeth. Thrashes his forehead against the sheets. All but screams, “Your cock. Please fuck me with your cock.” Tears well in his eyes. “I n-need it, need you to fuck me, please fuck me like a slut, please.

He can feel the danger emanating from Katsuki before anything happens. Then suddenly he's empty and it's awful, right before rough hands flip him onto his back again. One palm on his chest, pressing, putting Katsuki's weight into it, and the other shoving back into Izuku and yesss it's three fingers now, a beautiful stretch with a sting and it's all Izuku's ever wanted.

“I don't think so,” snarls Katsuki, driving in until the tight ring of muscle protests against his knuckles. Izuku yells. Squirms. Gasps as Katsuki applies more pressure on his lungs. “Fuck you like a slut? Hell, no.” His fingers crook, dig into Izuku's prostate and he can’t help the scream or the tears leaking from both eyes. Katsuki hovers over him, breathing hard, eyes wild. “Ain't gonna fuck you like that. Cuz you're mine.

This is better than any wet dream Izuku's ever had. He chokes when Katsuki fucks his hand into him again.

“Mine,” the mercurial blond grits through his teeth. “That's how you're getting fucked. Whether you're Izuku, Deku, a damn nerd, a whore—you get fucked like you're mine. I fuckin' own this ass now. Understand?”

God, he's so close—

Katsuki’s hands slides down, making Izuku wheeze as he presses into his stomach. Then slips under and tugs his balls, just hard enough to make the orgasm at the tips of his fingers fall out of reach. A loud, desperate cry flails out of Izuku.

“Answer me,” demands Katsuki.

Izuku breaks.

“Yes,” he sobs, frustrated tears streaming down his cheeks. “Yes, yes, I'm yours, Katsuki, just yours!”

A sharp intake of breath. Those harsh fingers ease up, and Izuku feels fresh tears well up in response. Then the hand is gone and he's clenching around nothing and why, why—

The rustle of sheets. Warm, dry hands cup his face as Katsuki positions himself between his legs. Raining damp kisses over Izuku's face, thumbs rubbing his cheeks over and over. Izuku pants through the agonizing frustration to see Katsuki looking at him with pure, unadulterated wonder.

“Again,” he rasps. Izuku gurgles out, yours, but Katsuki shakes his head and kisses him. Soft, lightly brushing his tongue over his lips, his teeth. “My name, Izuku. Say it again.”

Oh…

“Katsuki,” says Izuku. His chest burns when Katsuki’s eyes widen, his breaths coming faster. Izuku tries again. “Katsuki, please, I'm yours.”

Just an explosive exhale, and those rough lips on his. Tasting, taking, worshiping. Izuku greedily drinks it all in, because it's Kacchan, it's Katsuki, which means it's everything.

He hasn't forgotten his own need, however; far from it. Slinging one arm around Katsuki's neck, Izuku uses the other to slip between their bodies. Hands sliding through copious amounts of lube on his ass, then grazing over Katsuki's cock, nestled so heavy between his legs. Stroking, swallowing Katsuki's moans, wrapping his fingers around and guiding him down, forward, inside.

For a moment, Katsuki hesitates. Just the blunt, hot head of his dick pressing against Izuku's neediest place. Then Izuku wriggles his hips, pops him in, and everything else shatters, fodder in their past.

It's so easy. A slick, smooth slide in, bottoming out so fast that Izuku can hardly breathe. He digs his heel into the small of Katsuki's back, pressing more, harder, deeper. It's impossible yet it's all he wants.

“Fuck,” pants Katsuki.

Izuku nods, feverish. “Mine,” he whispers. He's so full, stretched and seated exactly where he wants to be. Home. Again.

Callused hands on his neck. Hot, brief kisses, like Katsuki's trying to find his footing. Then slow and simple and soft.

It's Izuku who moves. Rolls his hips, hissing, “Hurry up, fuck me,” and Katsuki obeys like he’s helpless. Slams into him, pulls out with a sweet drag, then fucks back in. Hard. Steady. Pulsing and hot and so alive that Izuku wants to drown in him. It's so goddamn good and not enough still.

Decided, Izuku briefly stills him with both of his legs going tight. Then, with a roll, flips them over, gathering his feet under him, nearly allowing Katsuki to fall out before he grinds back down, heavy. Using his legs to their full advantage, riding him like it'll be their last chance.

Shit, Izuku.” Katsuki's hands tense on his thighs but he makes no move to take over. Flushed all the way down to his nipples. God. “Jesus, babe, yeah, do that. You wanna own me? Fuckin' take what's yours then, right into that greedy hole.”

Arousal floods Izuku's spine, shuddering, coiling, burning. Behind him, Katsuki's knees bend, giving him a little more stability. Izuku takes full advantage, throwing his hands back, gripping Katsuki's thighs as he rides, hard, breathless, sweating. Everything is slippery and scorching and he can't tell if the water on his face is tears or sweat.

Watching Katsuki is incredible. The way his eyes obsessively rake him up and down. How he bares his teeth like he wants to bite; when his hands skim over marks and bruises he's left along Izuku's torso. Clutching his arm, right above his wrist, above his tattoo. The smells of sex and lube and nitro-sweetheat permeate the room, spicing up the desperate creaking of the bed frame.

And Izuku is pointed. Seeking out his pleasure, fucking himself down so Katsuki hits that sweet spot nearly every damn time. His chest heaving, hot, moving too fast for the sweat to cool.

I love you so much.

“Katsuki,” he begs, licking his lips when the use of his name draws out a moan. “Touch me.”

Fuck.” The word croaks out. Katsuki scratches up his thigh, leaving welts. Wraps his hand around Izuku's cock, damp, and there's a brief moment where Izuku thinks, One pop and my dick's gone.

Somehow, it turns him on more. That sense of unrealistic danger, because yeah, there's no way. Not Kacchan.

Izuku trusts him with his whole being, from skin to soul.

And it's amazing, the feel of Katsuki's hand, firm and hot on his cock. Sliding along the length, gripping, his fingers occasionally teasing his balls until Izuku is a mess. His legs shake. His thighs burn. Every strike to his prostate wrangles a filthy moan out of him and he can feel Katsuki pulse in response.

“I'm close,” gasps Izuku, hunching over to fist the sheets and drive himself over that edge. The new angle makes him feel fuller. Katsuki writhes like he's losing his mind. “A-ah, fuck, Katsuki… Katsuki!

“Holy fuck,” is all Katsuki says before pinching Izuku's ankles, thrusting up into him until Izuku's teeth clack. “Fuck, fuckin' tight ass, fuck, shit.

“Yes yes yes yes yes…

Broken cries, moans, and Izuku tumbles over first, jerking himself off through it while Katsuki damn near breaks his bones holding on. He shouts, eyes clenched tight, practically spitting as he comes over Katsuki’s chest. Wringing out every ounce of pleasure, twisting his wrist, thumbing under the sensitive head as he cries and shudders.

Below him, Katsuki watches, eyes huge and hungry. “Oh my god, Izuku…”

It takes all of Izuku's wherewithal to dredge up the strength to remain upright. Hands clenched atop Katsuki's chest, lungs burning with every intake of breath. He feels the cock inside throb, twitch, and he whines in response.

Still, Katsuki doesn't move to finish, instead petting up Izuku's sides until he shivers. Whispering hoarsely, “Good job, baby, that was hot as fuck, holy shit. Fuckin' never seen a bitch ride so hard.”

Izuku pries his eyes open. Pleading. “Kacchan…”

“Yeah, sweetheart, I know.” Katsuki takes a deep breath. Tightens his fingers around Izuku's waist. Flexes them. Relaxes. “When you're good.”

The love he possesses for this man is going to kill him.

Izuku's throat throbs. “How do you want me?”

Crimson eyes burn bright. “How can you take me?”

Ahh, that's a good point.

Slow, gentle, Izuku lowers himself, unheeding of the sticky mess between them. He kisses Katsuki, tangles their fingers together. Pulls his hands back to his ass, tucks his face into his neck.

Breathes, “Like this.”

Katsuki squeezes his ass. It's the only warning Izuku receives.

Rough gripping. Hips grinding, fucking shallow and tight, compressing the air in Izuku's lungs as Katsuki controls his ass, shoving him down to meet his movements. Hot, humid breath in his ear. Izuku is so over-sensitive and sore and doesn't give a damn. It's the kind of rough he needs, because it's precisely Katsuki's brand.

“Oh, fuck,” groans Katsuki. He snarls and bites at the first mark that started it all. Izuku welcomes the blessed soreness, the sharp teeth and muscle-deep bruising. “Fuck, Izuku… you feel so fucking… nngh…”

Every part of him feels swollen and sore. Izuku is really just along for the ride at this point, and he loves it, every excruciating, wonderful mile. Tonguing sweat from Katsuki's throat, clutching his biceps, sucking down brief pockets of air while Katsuki’s hips start to become sloppy and uncoordinated.

Then there's that telling tension. Katsuki hissing, “Fuck, fuck, hold on, babe, shit, fucker.” Nonsensical swearing before he jerks into Izuku, hard, abusing the puffy rim of his hole one last time before he unravels while moaning his name like he's putting a curse on him. Izuku takes it all, every shiver, every twitch. Each cell in his body vibrates with the knowledge that he did this, he made Kacchan come undone, and it's everything he ever wanted and beyond all of that.

They come down gradually, together. Chests tight against each other as they recapture their breaths. No words left after so many have been said—just the sheer pleasure of the other's company, skin to skin contact.

Finally, Katsuki rasps, “Heavy nerd. Get off.”

Izuku grumbles a complaint but manages to peel himself off. Rolls onto his side and oh, yeah, that's actually a good idea. The air he's breathing now is sweet and cool.

Within minutes, he's actually cold. Izuku starts to sit up and winces at the soreness.

Katsuki huffs. “Damn it, Izuku, you dick.” Before Izuku can even drop his jaw, Katsuki grabs one of the tossed shirts and pushes him back down. Wipes him clean. Scoffs. “Probably shoulda used a condom, shit.”

Izuku frowns. “I'm clean.”

“No shit. I meant for the mess, dumbass.”

Humming softly, Izuku wriggles his hips. Grins when that earns him a glare. “Mm, I like it though. Makes me feel like I'm really yours.”

Katsuki's breath hitches. His eyes haze for a moment. “Ah… yeah. That's hot.”

At least there isn't any regret. Izuku tugs Katsuki's arm and doesn't relent until he lies down next to him. It's a pleasant, welcome surprise when Kacchan pulls him close and shifts a leg between his.

“So,” he starts, somewhat shyly. “What's this make us?” At Katsuki's blank look, Izuku feels he might as well pull the trigger. “Are we dating?”

Flatly, Katsuki says, “If we're gonna date, we'll need a bigger place.”

Izuku's eyes pop wide open. “I… huh?”

“A bigger place,” Katsuki repeats like he's a moron. “You're gonna replace most of that nerdy shit you lost, I can tell. And you're fucking out of your mind if you think I'm letting you put all that shit in the living room, or worse, the bedroom. I don't need the ghost of our goddamn mentor judging me for being dicked down by his successor.”

Bright red colors Izuku's face. He fiddles with Katsuki's fingers. “So… you really wanna… I mean, you trust me to make bottoming good for you?”

A steady gaze meets his. Then a quiet voice. “Ain't anyone else I would trust, Izuku.”

Sheer affection overwhelms Izuku. He grasps Katsuki's jaw with both hands, peppering him with chaste kisses that Katsuki tolerates for a few seconds before deepening them. A happy hum rumbles in Izuku's chest.

He can easily get used to this.

***

Adjusting to living with Kacchan is surprisingly easy. Maybe because they sort of already lived together in the dorms, but Izuku isn't sure that's all there is to it. It just feels smooth and natural. Of course, there are hiccups along the way, and when it comes time to find a bigger apartment, they bicker ceaselessly over location, amenities, and space.

They make it work, though. Turns out talking really does make a difference.

When they have a new two-bedroom to call their own, Izuku is thrilled to begin rebuilding his heroes collection. What was once All Might begins to expand to others, including their friends… and Dynamight.

Katsuki is thoroughly embarrassed but only bitches about it when he needs to set foot in the room.

Also, Izuku really likes their new bed. He'd like any bed, really, as long as Kacchan's in it with him. But this one is nice and comfy and withstands their rough sex. Extra bonus.

About a week into living there, Izuku finds himself tracing invisible lines along Katsuki's fingers. Almost like something should be there but isn't.

“Kacchan,” he murmurs. “I wanna get another tattoo.”

Katsuki snorts into the pillow. “To match the one you don't even remember getting?”

“It doesn't have to match. I just think I'd like another.”

“Hmm.”

Izuku squeaks when Katsuki's hand slides down his thigh. He squirms, then gasps when a rough finger traces across his upper leg. Over and over, like he's tracing something.

Softly, Katsuki says, “If you're that intent, I have an idea.”

Izuku blinks. “What's that?”

A slow, sly grin spreads Katsuki's lips. He grips Izuku's thigh hard enough to bruise… and enough to make Izuku's tired cock twitch. “Tell me, Izuku, how d'you feel about being branded?

***

Sometimes, Izuku feels like he remembers something that hasn't happened yet. Then the incident will come and go, and it'll be totally different from what he expects. It's always a little jarring, yet ultimately harmless.

At the very least, Kacchan never calls him crazy. It takes two years for him to grudgingly admit that he occasionally experiences the same thing.

Izuku doesn't mind, nor does he feel lied to. Katsuki's always kept to his own pace. All Izuku cares about is whether or not his boyfriend trusts him.

As it turns out, that becomes the foundation of their relationship over the years. So when it comes time for them to regain some lost memories, well. The unorthodox paradox syndrome comes full circle, and the laws of space-time remains satisfied.

***

“Babe! Come look at this.”

“What's—ah! Kacchan, your hand!”

“Oh my god, it's fuckin' fine. See? Tattoo's still there.”

“Kacchan, I'm not worried about your ring tattoo when you come home with a broken hand.”

“Sprained, you dick, not broken. Look at this.”

“That's… oh. Is that the villain the government put out an All Alert for?”

“Mmhm. Stupidest fuckin' name ever, too.”

“Uh huh, Great Explosion Murder God Dynamight.”

“Fuck you, at least my name makes sense with my quirk. The fuck kinda name is Stopwatch?”

“Kacchan, be nice.”

“Izuku, stop being a simpering fuck.”

“Okay, but you know I simp for you first, so— mmph!”

“... shut up. Idiot.”

“Heh. I love you, too.”

“Yeah. You fuckin' better.”

 

✧ END ✧

Notes:

I am just... AMAZED that this even happened. Much less that I've gotten the sort of comments that I have, both encouraging and critical. I've never had such interaction with a fanfic between others and it's been a WILD thing to see.

Many thanks to Fitzrovia (check out her work!!!) for helping me talk through points I got stuck on.

Also, TheWitchling for kindly DMing me on Twitter to point out errors. 💜

And especially to the Twitter peeps who have been engaging with the teasers. It's been so fun to see!

The Twitter poll ended in a draw, so the next project will be a surprise. I have a few ideas I wanna look over before deciding what to tackle. I may just go back to "Ready, Set, Transpose!" in the meantime though lol.

I'd love to know which chapters were your favorites, which smut scenes got to you the most - really, anything! I'm just so, so happy to be writing BKDK up until now.

The next big project should bring my BKDK word count to over 700,000 😭 WTF

Have a great rest of your day! 💜💜💜

Notes:

You can find updates, screencaps of WIPs, and more on my twitter.

Series this work belongs to: