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Kiyoomi groans, rolling over in bed and pulling the covers up over his head. He can tell from the weak morning light coming through the curtains that it’s way, way too early to be up. Normally, his body’s pretty good at sticking to his night owl schedule, so then why the hell was he awake?
Kiyoomi keeps his eyes tightly shut, trying desperately to fall back to sleep. It’s an off day for their team; there’s no way he wants to be up this early. He hears the rustling of sheets as Atsumu readjusts his sleeping position and feels the bed lightly shake. Between that and the suddenly pressing urge to piss, Kiyoomi realizes he’s not falling back to sleep anytime soon.
Fuck.
He peeks his eyes open and is confused to see he’s on the right side of the bed, when he normally claims the left side. However, memories of the particularly intense three rounds of sex they had before bed comes back to Kiyoomi, causing heat to creep up his neck. He vaguely remembers being so blissed out and dumb with pleasure by the end that he doesn’t even know if he came during the last round. They must’ve just been too tired to do anything but collapse anywhere on the bed after cleaning up. As Kiyoomi clambers out of bed, he’s expecting to feel a dull ache as he bottomed for all three rounds, but he feels nothing unpleasant. Not that he’s complaining. He groans again, feeling heavy, like he's being weighed down more than usual. He must just be feeling exhausted after last night.
Despite being wide awake now, Kiyoomi keeps his eyes shut as he wanders into the bathroom and pisses, in some last-ditch attempt to stave off the morning. They’ve lived here for over a year- just renewed their lease- so he’s easily able to use muscle-memory to navigate the bathroom. Still, Kiyoomi is startled when his hipbone bangs into the corner of the sink countertop. He’s never, ever hit the corner of the countertop with his hipbone as he’s always been slightly too tall for the heights to line up. He hisses, his eyes flying open as he rubs at his hip.
Kiyoomi stills when he realizes two things at once: He’s wearing Atsumu’s sweatpants and that is most certainly not his pale hand rubbing over his hip bone. His hand is tanned, his fingers shorter and thicker, but still nice. Kiyoomi recognizes them, because they’re fingers he’s had inside of him more than times he could ever count. They’re Atsumu’s.
Kiyoomi’s heart is suddenly in his throat as he slowly turns and looks into the mirror. What he sees is Atsumu’s startled face, mouth hung open.
Kiyoomi gasps, taking a sudden step back and almost tripping. For a moment, he just stands there and breathes heavily, watching as Mirror Atsumu’s bare chest heaves. Kiyoomi’s heart races as he steps forward again and raises a hand, watching as Mirror Atsumu raises his. Kiyoomi runs his hand through his hair, Mirror Atsumu copying, and sure enough he feels Atsumu’s soft hair, slightly thick from the bleach but still undeniably familiar.
“What the fuck,” Kiyoomi mutters, and it’s Atsumu’s warm voice that he hears.
Kiyoomi’s...in Atsumu’s body, and he can barely believe it.
And why should he? It’s fucking crazy. There’s no explanation for why Kiyoomi would wake up in the body of his boyfriend of over three years.
Then things start clicking into place. This body waking Kiyoomi up earlier than his would’ve, being on the wrong side of the bed, no dull ache from rounds and rounds of sex. It’s because...it's because…
Kiyoomi drags his eyes away from the mirror and exits the bathroom. His breath catches in his throat when he sees himself, his body, fast asleep on the side of the bed he normally sleeps on. Other Kiyoomi is laying on his stomach, head resting on one arm while the other is tucked under the pillow, his dark curls a stark contrast against the white pillowcase. Nothing looks too out of the ordinary; His skin is still pale and littered with beauty marks, and he looks like he’s sleeping like the dead. The only strange thing is that he’s lying on his stomach, a nasty habit that Atsumu has and Kiyoomi doesn’t. Vaguely, Kiyoomi remembers all the times he’s scolded Atsumu about how sleeping on your stomach can hurt your back and neck.
So that begs the question: If Kiyoomi is in Atsumu’s body, does that mean…?
Kiyoomi takes a deep breath, slowly inching toward the bed until he’s stood beside Other Kiyoomi. He reaches a hand out- Atsumu’s fucking hand- and presses it against Other Kiyoomi’s arm. Other Kiyoomi whines, burying their face deeper into the pillow. Kiyoomi freezes until Other Kiyoomi settles, then he pokes his arm again.
“Fuckin’ tired, Omi,” Other Kiyoomi grumbles, in a slurred Kansai dialect.
“Atsumu?” Kiyoomi questions, retracting his hand.
“Baby, ‘m sleepin’,” comes a soft reply from Other Kiyoomi’s- Atsumu’s- mouth.
Kiyoomi breathes a sigh of relief. Okay. Okay. At least Kiyoomi isn’t alone in whatever fucked up thing is going on. However, because Atsumu’s in Kiyoomi’s body, it’s going to take a bit to get him to actually wake up.
“Atsumu, look at me,” Kiyoomi demands.
“Mmmm,” Atsumu hums, voiced muffled by the pillow.
“Atsumu, fucking look at me.”
“What,” Atsumu mutters, lifting his head from the pillow and finally meeting Kiyoomi’s eyes.
Atsumu’s eyes instantly widen and he gasps, sitting up at record speed as he scrambles away from Kiyoomi.
“Hey, it’s okay,” Kiyoomi says quickly, coming closer.
“What the hell? What-” Atsumu cuts himself off, staring at Kiyoomi like he has two heads, but he might as well be considering how crazy this is.
“Atsumu,” Kiyoomi tries again. “It’s me. It’s Kiyoomi.”
It’s strange, watching his own face relax at his words.
“Kiyoomi?” Atsumu whispers.
“Yes, it’s me.”
“No. No. My Kiyoomi doesn’t fuckin’ look like me. Fuck, I must be dreamin’. Am I high? Am I fuckin’ high? I don’t even do drugs, I-”
Atsumu starts panicking, so Kiyoomi sits on the bed and breaks into his thoughts.
“Atsumu, listen to me,” Kiyoomi says firmly. Atsumu’s mouth snaps shut and his eyes widen. Well, if Kiyoomi had any doubt it was Atsumu in his body, he’d know it was true based on how expressive he was making Kiyoomi’s face look.
Kiyoomi swallows. “I don’t know what’s going on, but when I woke up I was in your body, and it turns out you’re in mine.”
Atsumu laughs in disbelief, then stills. “Why do I sound like…?”
Suddenly, Atsumu bolts from the bed and practically dives into the bathroom, almost tripping on the rug in front of the sink. Kiyoomi stands and follows him.
Atsumu screams as he takes in his appearance, hands flying to his hair.
“Omi?!” Atsumu exclaims, looking at Kiyoomi. “Why are…?”
“I don’t know,” Kiyoomi returns. Kiyoomi watches as Atsumu turns back toward the mirror, his fingers ghosting over every inch of his face, and the moles dotting over his right brow.
After what feels like hours, Atsumu seems to finally accept that he’s not dreaming.
“We should go to the hospital,” Atsumu suggests, exiting the bathroom.
Kiyoomi rolls his eyes as he follows him out. “And be committed for insanity? No thanks.”
They both sit on the edge of the bed. Kiyoomi notices with fascination that Atsumu still does his nervous gesture of tapping his fingers against his knee.
“Fine, the hospital is ruled out. Maybe we should call ‘Samu and see if he switched with ‘Kaashi-kun.”
“Excuse me?”
“I don't know! Maybe everyone switched with their partners!”
“That’s ridiculous!”
“Right, ‘cause other people switchin’ bodies would be ridiculous.”
“Atsumu,” Kiyoomi says firmly, cupping his cheeks. Atsumu quiets. “We can’t tell anyone about this, because they won't believe us. We just need to figure out how to switch back.”
Kiyoomi is surprised by the sensation of his own skin, which is soft and smooth. He’s used to cupping Atsumu’s face, which is always stubbled because Atsumu doesn’t like to shave every day. However, Kiyoomi likes that sensation, so it’s unnerving for it to feel any other way.
Atsumu finally nods, so Kiyoomi removes his hands.
Atsumu asks, “Ya ever seen Freaky Friday, that American movie?”
“No, I haven't. What’s it about?”
“In the movie, the ma and daughter switch bodies. They only get to switch back after they learn a lesson. Maybe that’s the key to us switchin’ back.”
Kiyoomi frowns. “You think we need to learn a lesson to switch back?”
Atsumu’s eyes shimmer with a confidence that’s unmistakably Atsumu’s, even through Kiyoomi’s dark eyes. He says, “Think about what we were doin’ before we went to sleep.”
Kiyoomi shakes his head. “What?”
Atsumu whines, “Ya don’t remember?”
“No, I don’t.”
Glaring, Atsumu says, “You really don’t remember us havin’ sex like a million times?”
Kiyoomi rolls his eyes. “Of course I remember that, but what the fuck does it have to do with this?”
Atsumu smirks. “Do ya remember what ya said?”
“Atsumu.”
“Fine! In between rounds I asked if ya wanted to top for the next one, but ya said, “If you knew how good it felt for you to fuck me you wouldn’t be asking that.””
Kiyoomi’s cheeks burn. He vaguely remembers saying that as he was still catching his breath and his brain was still melted from his last orgasm. Under no other circumstances would he willingly stroke Atsumu’s already inflated ego.
“I never said that,” Kiyoomi states flatly. Atsumu pinches his arm lightly, and Kiyoomi bats his hand away.
“Yeah ya did. What I’m sayin’ is that maybe we switched bodies so that I could actually feel how good it is for me to...fuck me. Or whatever.”
Kiyoomi tries to tell himself that murdering Atsumu in this moment wouldn’t be worth the clean up. And that he loves him very much, of course.
“Atsumu, I didn’t say that so we would fucking switch bodes. Do you actually think that we would switch back after having sex like this?”
Atsumu doesn’t answer, so Kiyoomi’s eyes trail lower. And fuck, Atsumu’s sweatpants are slightly tented.
“Are you seriously hard right now?”
“I can’t help it! I’m...I’m thinkin’ about it.”
Kiyoomi is about to call him an idiot, but then Atsumu’s eyes go hooded and he bites his lip. Atsumu runs a hand over Kiyoomi’s thigh, causing Kiyoomi’s original retort to die on his tongue. Atsumu's hand is so warm on his leg, even with a layer of fabric separating their skin.
“What are you thinking about?” Kiyoomi wonders, voice lowering.
“I’m thinkin’ about kissin’ ya,” Atsumu murmurs, his wandering hand rising higher. “I’m thinkin’ about playin’ with yer nipples.”
Atsumu brushes Kiyoomi’s right nipple with his thumb. Kiyoomi shudders.
“You’re always sayin’ my nipples are so sensitive, Kiyoomi,” Atsumu reminds him.
It’s true. Atsumu’s entire body is sensitive, and his nipples are no exception. Kiyoomi loves plucking them, and loves sucking on them. Anything to draw out Atsumu’s needy whines. And to be on the receiving end of that is...is…
Atsumu squeezes Kiyoomi’s nipple between his thumb and index finger. Kiyoomi feels a thrill zip up his spine at the sensation. His own body has never felt like this, like a live wire, like the smallest touches could cause such intense pleasure.
Kiyoomi can’t help it. As Atsumu continues playing with his nipple, his cock starts filling in his sweatpants.
“Shit, Atsumu,” Kiyoomi sighs.
Atsumu purrs, “I’m thinkin’ about yer thick fingers stretchin’ me open just for me to take yer cock. And how it still won’t be enough because this body's always so fuckin’ tight.”
Kiyoomi closes his eyes, imagining what it would be like to sink into his own body. The reason he said that to Atsumu is because, while he loves fucking Atsumu, he loves being fucked by Atsumu just a smidge more. Kiyoomi has always been the tighter of the two, despite Atsumu’s cock being thicker. No matter how much times they have sex, the stretch always borders on painful, which just makes it feel so much better. Kiyoomi has only ever thought about how he feels when Atsumu fucks him, that he hasn’t really thought about how Atsumu specifically feels when fucking him. To Atsumu, it must feel so fucking hot and tight and all consuming.
“C’mon, Omi,” Atsumu leans close to whisper in his ear. Kiyoomi’s body shivers at the feeling of Atsumu’s lips brushing against his ear. Shit, this body is so sensitive. “Aren’t ya the least bit curious?”
Kiyoomi feels heat flood his body at those words, because this shouldn’t be something that interests him but the forbidden-ness of it just makes it so much hotter. This is wrong, right? Then why is Kiyoomi’s heart racing?
Atsumu presses a kiss to Kiyoomi’s cheek, then places another one at the corner of his mouth. Kiyoomi sighs, blindly reaching his hands out to hold Atsumu’s waist, surprised again when the waist he’s grabbing is tinier than usual. However, it feels good, like Kiyoomi’s hands are so big they could wrap around that tiny waist like it was nothing.
“What do ya say, Kiyoomi?” Atsumu asks.
Kiyoomi doesn’t need to give it another thought. He commands, “Kiss me.”
So Atsumu does, capturing Kiyoomi’s lips in a searing kiss. Kiyoomi doesn’t know whose mouth parts first, but suddenly Atsumu’s tongue is in his mouth. This part actually doesn’t feel too different from normal, if Kiyoomi keeps his eyes shut. It’s strange when his hands slip into Atsumu’s hair and he feels his own curls, but then Kiyoomi remembers how much he likes when Atsumu tugs on his hair. Kiyoomi pulls roughly at Atsumu’s hair, causing him to groan into the kiss. Atsumu’s fingers are at Kiyoomi’s nipples again, playing with them as their kisses grow heated and sloppy.
It’s overwhelmingly good, and Kiyoomi has to break apart from the kiss to moan. It’s Atsumu’s broken voice he hears, which practically creates a Pavlovian response in Kiyoomi at this point, as the sound goes straight to his cock.
“Fuck, get higher up on the bed,” Kiyoomi directs Atsumu, who eagerly detangles from Kiyoomi and settles back down further up the bed.
Kiyoomi stands so he can take off his sweatpants and collect a bottle of lube from the nightstand. He drops the bottle somewhere on the bed so he can settle on top of Atsumu as quickly as possible, pressing a thigh between his legs to feel his bulge. Atsumu pulls Kiyoomi into another, slower kiss.
“Mmm,” Atsumu hums, bucking his hips up to rub himself against Kiyoomi’s leg. Kiyoomi indulges him, pressing his leg down firmly. A fleeting thought about Atsumu getting off on rubbing against his own massive thighs crosses Kiyoomi's mind, and a mix between want and shame burn inside him. He shouldn't want this, shouldn't be getting ridiculously hard over thoughts like this, but the white hot flame of guilt in his gut melts into toe-curling pleasure as Atsumu continues grinding on his leg.
Their hands wander each other’s chests and shoulders and arms more than usual, fascinated by how it feels to touch their own bodies. At first glance, they’re both professional athletes over six-foot, so they can’t be that different, right? However, after years of dating and exploring every inch of each other's bodies, Kiyoomi knows every small difference.
Atsumu’s chest is broader, the narrowing of his waist not as severe. He’s hairier, with dark chest hair and a happy trail that Kiyoomi loves nuzzling before sucking him off. His thighs are larger, despite Kiyoomi’s best efforts receiving the ball more frequently during games. His cock isn’t as long as Kiyoomi’s, but it’s bigger, too big to fit comfortably in Kiyoomi’s mouth or ass, but the challenge just makes it better. Kiyoomi has been attracted to Atsumu’s body long before they fell in love, but there’s something exciting and new about touching this other body.
Atsumu squeezes his ass, kneading the flesh through his boxer briefs. Atsumu’s ass is, of course, bigger than Kiyoomi's, so Atsumu pays more attention to it than usual. It’s exactly what Kiyoomi does during sex, and it feels fantastic. Atsumu readjusts them slightly so that their hips are more aligned, rocking his hips up.
Kiyoomi gasps, breaking the kiss.
“There,” Atsumu sighs, digging his heels into the sheets to do another controlled, slow thrust upward. Kiyoomi moans loudly, burying his face in Atsumu’s neck.
“Yer neck’s sensitive,” Atsumu tells him, voice breathy. Atsumu has said this before, when he’s sucking marks on Kiyoomi’s skin there. Kiyoomi’s body might not be as sensitive as Atsumu’s, but his neck is the exception. Kiyoomi takes the hint, biting down hard on Atsumu’s neck.
“Oh fuck, fuck-” Atsumu gasps, building up some sort of rhythm of bucking his hips up as Kiyoomi bites and sucks marks onto his neck. Atsumu shivers underneath him as Kiyoomi sucks on a mark he already made. “Christ, Omi…Fuck, shit.”
It’s strange, hearing Kiyoomi’s voice so much, when Atsumu is the more talkative one during sex. However, Kiyoomi thinks about Atsumu pleasuring him like this, so good and so thorough that Kiyoomi loses all sense and starts babbling. It’s happened before, it even happened last night, so when Kiyoomi thinks of it like that, he starts grinding down to match Atsumu’s pace. Sparks of pleasure shoot up his spine and his cock is throbbing in his boxer briefs at how good the friction feels.
Kiyoomi groans low and rough into Atsumu’s neck, mindlessly humping down as he really does start to lose all sense, his only goal now that he’s so hard being to come.
Suddenly, Atsumu stops rocking his hips up. Kiyoomi frowns, lifting his head up. His stomach twists when he’s met with his face, splotched red with glazed over eyes.
“Need you,” Atsumu begs. “Please.”
Kiyoomi’s heart stutters at the request, but he slowly lifts himself so that he can comply. Atsumu’s right, they need to take this all the way before the pleasure fades and they grow too self-conscious of what they're doing. He peels off his boxer briefs and tosses them off the bed. He also roughly pulls Atsumu’s sweatpants and underwear down in one swift tug, revealing Kiyoomi’s pink, curved cock that’s already leaking all over itself. Atsumu sighs as he looks down at it.
“Look how pretty ya are, Kiyoomi,” Atsumu murmurs, meeting his eyes. In Kiyoomi’s body, his gaze is intense, and it makes Kiyoomi’s heart beat loudly in his chest, and neck, and ears. Then, Atsumu’s eyes graze over his own body, biting his bottom lip so hard Kiyoomi think he’s going to break the skin.
Kiyoomi accuses, “You’re into this because you’re full of yourself.” Atsumu's eyes widen in shock as Kiyoomi nudges his legs apart. Kiyoomi smirks. “Have you thought about this before, Atsumu? About fucking yourself?”
“No,” Atsumu whines, cock twitching as Kiyoomi leans down and ghosts his breath over it.
“No? Are you sure? You were practically begging me to fuck you while I’m in your body.”
“Wasn’t,” Atsumu mumbles, his eyes fluttering closed as Kiyoomi sucks a bruise onto his thigh, another area of Kiyoomi’s body he knows is sensitive.
“Well then,” Kiyoomi says. “Guess I’ll have to fuck you so good you’ll admit to being a sick fuck.”
Kiyoomi doesn’t give Atsumu a chance to respond, taking his cock in his mouth and burying it in his throat in one smooth motion.
“Fuck, oh my God,” Atsumu exclaims, hands flying to thread themselves in Kiyoomi’s hair.
Kiyoomi hums, bobbing his head up and down to continue taking Atsumu to the hilt. Kiyoomi doesn’t ever deepthroat; his gag reflex won’t allow it. But Atsumu...Atsumu doesn’t have one, always deepthroating Kiyoomi so well that he has Kiyoomi coming in record time. Even if Atsumu wasn’t a moaning, writhing mess, Kiyoomi knows firsthand how good this feels. Something about being able to make Atsumu feel so good sparks a warm burst of pride in Kiyoomi’s chest, and he starts to realize why Atsumu is so cocky, if he often feels like this. And yeah, he acknowledges that he tastes good, and the weight of his cock is perfect in Atsumu's mouth. It makes sense why Atsumu practically begs to blow him every chance he gets. Kiyoomi makes a mental note to demand Atsumu thank him the next time he blows Kiyoomi.
"You like- hah- it sloppy," Atsumu breathes, breaking into his thoughts. Heat pricks Kiyoomi's skin, because Atsumu is right. Kiyoomi has never explicitly said it, but he realizes he really does love when Atsumu makes it as wet and messy as possible. Some depraved part of Kiyoomi revels in it. So, Kiyoomi works on adding as much saliva as possible, toes curling at the wet sounds his mouth makes taking his own cock. Kiyoomi also likes when Atsumu's tongue presses against his frenulum, so Kiyoomi works that in. Atsumu's moans grow filthier and he starts shamlessly bucking up into Kiyoomi's mouth. In this body, Kiyoomi doesn't have to stop him. Brain melting pleasure comes from knowing how good Atsumu feels right now, and being able to make Atsumu feel even better because of how well he knows his own body.
Kiyoomi rests his hands on Atsumu’s abdomen, feeling the way the muscles tighten and flex as Atsumu gets close. And when Atsumu starts arching off the bed, Kiyoomi pulls off with a wet pop. Atsumu collapses back onto the bed, whining at the loss.
“Your mouth was made to take my cock,” Kiyoomi tells him, reaching for the lube. “Nothing but a cock sleeve for me to use.”
Atsumu moans, his eyes closing again and his cock leaking and smearing precum on his stomach. It doesn’t matter what body Atsumu’s in, he still loves a seemingly contradictory mix of praise and degradation. Kiyoomi might not babble like Atsumu does, but he loves using well-timed dirty talk on Atsumu just to see his reactions. Fondness blooms in his chest; Kiyoomi loves this man, and how undeniably compatible they are.
Kiyoomi still smirks, pouring some lube on his hand and rubbing it between his fingers to let it warm up. Kiyoomi starts by grazing his thumb over Atsumu’s rim. Atsumu sighs, and Kiyoomi says, “Do you feel that ache, Atsumu? Do you feel what you do to me?”
Atsumu keens, his hips squirming and hole fluttering beautifully. He mumbles, “Feels so good, Omi. Makes me want more.”
Kiyoomi knows that feeling exactly, so he obliges, inserting one finger and massaging Atsumu’s rim with his thumb to ease the stretch. Atsumu groans, pushing back onto Kiyoomi’s finger.
“Do you feel how thick your fingers are, Atsumu? How even one finger is almost too much?”
“Yes, God, feels so good,” Atsumu babbles, practically fucking himself on Kiyoomi’s finger.
And Kiyoomi knows Atsumu’s telling the truth. Kiyoomi loves having sex the morning after a particularly rough night, just to hit that dull ache again and again. It’s painful yet so fucking good.
“Let’s see how many more fingers you can take,” Kiyoomi drawls, inserting a second finger, slowly pumping his fingers in and out. Atsumu sucks in a sharp breath when Kiyoomi brushes over his prostate, moaning loudly and unabashedly when Kiyoomi continues hitting it.
Atsumu is too lost in his own pleasure to even notice Kiyoomi adding a third finger. If Atsumu was in his own, overly sensitive body, he would’ve already come from this alone. Lucky for both of them, Kiyoomi’s body can hold out long enough for what they want to do.
Eventually, Kiyoomi pulls his fingers out, his own cock too painfully hard to resist fucking Atsumu as soon as possible. Atsumu hisses, twisting his head back on the pillow. Honestly, Atsumu might not be stretched open as well as he should be. However, Kiyoomi’s body has a higher tolerance for pain, he was already still somewhat prepped from last night, and Kiyoomi honestly likes being fucked when he’s not completely ready. One of the things Kiyoomi loves about Atsumu is how caring and loving he is, which extends to prepping Kiyoomi, but sometimes Kiyoomi just has to tell him to hurry up and fuck him already.
Today, Kiyoomi is going to teach Atsumu why he gets impatient.
Kiyoomi pours lube on his hand and strokes himself to coat his cock. They only use condoms if Kiyoomi is being particularly fussy and wants easier clean up, but right now he wants both of them to feel everything. He wipes his hand on the sheets then grabs a pillow to shove under Atsumu’s hip. Kiyoomi doesn’t intend to go easy on him, so he might as well make the position as comfortable as possible. Kiyoomi then drapes himself over Atsumu, pressing their chests together, and kisses him deeply. Atsumu immediately returns the kiss, tugging on Kiyoomi’s hair, like he’s used to doing for Kiyoomi’s curls. Atsumu hooks his legs around Kiyoomi’s waist to keep him close, and it causes Kiyoomi’s cockhead to press against his hole. Atsumu moans into the kiss, eventually giving up on it because he’s breathing too hard. Kiyoomi kisses his neck instead, sucking another bruise as he lines himself up.
Kiyoomi’s own stomach is a mess of butterflies. He always forgets how good pushing into Atsumu feels until he’s about to do it again.
“Fuck me, please,” Atsumu practically sobs, and Kiyoomi wants him so badly it feels like it could kill him. He’ll never, ever get tired of resorting overly confident Miya-fucking-Atsumu to a begging mess.
“You want to be fucked?” Kiyoomi asks, slowly starting to sink into Atsumu- into his own body. “I’ll fuck you so good you won’t even want to return to your own body.”
“Please,” Atsumu begs, nails digging into Kiyoomi’s back. Atsumu has always liked scratching Kiyoomi’s back, seeing how the red marks contrast to his pale skin. And in Atsumu’s sensitive body? It feels even better.
Kiyoomi tries to breathe evenly as he continues pushing into Atsumu, but it’s so tight and so hot that he feels like he’s being suffocated. It’s by far the tightest fit he’s ever experienced, and it feels so unbelievably delicious that by the time he bottoms out he’s already teetering on the edge of his orgasm.
“O-Omiii,” Atsumu groans in his ear, gasping and clutching at his back. And Kiyoomi knows. He knows how good the stretch must feel to Atsumu right now, and Atsumu’s pleasure just makes Kiyoomi shake with the effort of holding off his orgasm. Does Atsumu always feel like this? So punch-drunk with pleasure the instant he sinks into Kiyoomi that it takes everything in him to not come on the spot?
“Atsu, I’m-” Kiyoomi cuts himself off, trying not to move.
“I know,” Atsumu sighs. “Just- just take a second.”
Kiyoomi does, focusing on his own breathing and how their chests are hot and already slick with sweat. Atsumu's hands become soothing on his back, and eventually, finally, Kiyoomi isn’t on the knife's edge anymore. He slowly pulls out, and slams back in, causing them both to gasp. As he continues moving in and out, building up a steady rhythm, Kiyoomi remembers that this typically feels even better when his legs are hitched up. So, he reaches back and nudges Atsumu’s legs off his waist. When Atsumu's legs fall away, Kiyoomi keeps one hand under Atsumu’s head to hold him close, but takes the other and pushes Atsumu’s left leg up and against the sheets, and there-
Atsumu screams, arching off the bed and desperately clawing at Kiyoomi’s back again. Kiyoomi fucks him faster, slamming into him with as much force as he can manage. Their headboard bangs against the wall, and the entire bed rattles and creaks with the motion. Their hips are snapping together so forcefully it's painful, and Kiyoomi knows they'll both have bruises later, but he can't find it in him to care.
Kiyoomi leans close to Atsumu's ear and whispers, "Feels good, yeah? Your own cock splitting you open?"
"Omiii," Atsumu gasps. "So good, so good, so- hah- good."
Kiyoomi kisses him, but it's too rough and Kiyoomi tastes blood. Kiyoomi pulls back, expecting to see Atsumu's lip bleeding, but it's his own face that he sees. Atsumu opens his eyes, and they're glassy with tears. They've never admitted it out loud, but they both know that Kiyoomi has always gotten strangely turned on from making Atsumu bleed and cry, which probably has to do with the fact that Kiyoomi loves making a mess of Atsumu. However, even though it's his face he's looking at, Kiyoomi still feels butterflies from those dark lashes clumping together with tears and blood smeared on that pink bottom lip. Asumu was right earlier; Kiyoomi is pretty. Some twisted part of Kiyoomi thinks his face looks gorgeous like this, wrecked and blotchy and stained with tears. The sight becomes too much, and Kiyoomi buries his face in Atsumu's neck again. He wants to make Atsumu admit that he's a sick fuck for enjoying this, but who is he to talk? He's getting off to fucking his own tight hole, to his own pleading gasps and facial expressions. They're both depraved, but the pleasure is too intense for that to feel like a bad thing.
Far too soon, Kiyoomi is back to being on the crest of his orgasm, heat pooling in his gut, so he releases Atsumu's leg to wrap a hand around his cock and stroke him quickly. He knows his cock has always fit perfectly in Atsumu's hand.
“M’comin’, m’comin’,” Atsumu sobs, his entire body shivering and trembling as he comes on Kiyoomi’s hand. Atsumu squeezes around Kiyoomi, who sees stars as he comes hard inside of Atsumu. It feels fucking endless, the way Kiyoomi keeps fucking Atsumu as he comes, riding out his own pleasure. It’s by far the most intense orgasm of his life, the pleasure expanding in his entire body. Finally, Kiyoomi’s hips stutter to a stop as he comes down from his high. They’re both breathing hard, groaning lightly on the exhale.
After a few minutes, Atsumu’s hand finds Kiyoomi’s hair again as he laughs. “Holy shit. Never came so hard in my life. I can see why ya said that now.”
Kiyoomi grins, kissing Atsumu’s neck again. “Told you.”
Kiyoomi lifts his head to look at his boyfriend. While he sees his own face, that soft, adoring expression is undoubtedly Atsumu’s. Kiyoomi kisses him, humming. He pulls out, making sure to go slow so that Atsumu can adjust to the loss. He imagines Atsumu is too boneless to clean them off like he normally does, so Kiyoomi takes the task over. It takes the last of his remaining energy to grab a damp, warm towel and run it over himself and Atsumu. Atsumu sighs, closing his eyes and looking dangerously close to falling asleep.
“Get up, Atsu,” Kiyoomi says softly. “We need to change the sheets.”
“M’tired. Sleep first, baby,” comes Atsumu’s slurred reply.
And Kiyoomi can’t blame him. He remembers how exhausted his own body becomes after sex, especially so early in the morning. So, Kiyoomi crawls into bed beside him, in Atsumu’s typical spot. He pulls the covers up and over them, and it’s warm and cozy. Kiyoomi cuddles into Atsumu’s side, and Atsumu wraps an arm around him as Kiyoomi’s rests his head on his chest.
“We didn’t switch back,” Kiyoomi whispers, shutting his eyes. “Guess your theory was wrong.”
Atsumu chuckles. “Still worth it.”
Kiyoomi smiles into Atsumu’s skin, thinking that he was able to go through with it and explore those desires because of how much he trusts Atsumu.
“I love you. It doesn’t matter what body I’m in,” Kiyoomi tells him. Atsumu kisses his forehead gently.
“I love you too, baby. Don’t worry. No matter what happens, we’ll be okay.”
They must’ve fallen asleep again, because when Kiyoomi blinks his eyes open, the light coming through the curtains is far stronger, closer to early afternoon.
He starts to get up, but then he feels a dead weight on his right half, and that familiar soreness down below. Startled, he glances to his right, seeing Atsumu- in the right body- asleep on top of him. Kiyoomi smiles, relaxing back and breathing out a sigh of relief. He lets Atsumu sleep a little longer as he quickly falls back to sleep himself, but true to themselves, Atsumu is wide awake barely ten minutes later, excitedly waking Kiyoomi back up to tell him the good news.
They never figure out what caused them to switch bodies. Hell, maybe they both just had the same bizarre dream, but Kiyoomi begrudgingly admits that Atsumu was right. They did learn something about each other that day. And maybe, just maybe, in the safety of their bedroom, they sometimes role play and pretend it happened again.
However, one thing remains the same: The love and trust they’ve built between each other is undeniable.