Tamaki loves everything about Mirio.
Everything: every inch of his sun-kissed skin and every scar that crosses it. He loves his blue eyes, his smile, his kind heart. He loves his hair, and his hands, and his feet.
He also loves his ass.
It's such a truly beautiful ass: round and plump and thick in his hands when he kneads the flesh in his fingers.
When Mirio told him what he wanted to do this year, the hardest part was to decide in which position would he take him. He likes to fuck Mirio on his back; likes to devour every expression on his beautiful face. He likes to have him at close hand, so he can kiss him... And since kissing would break his character this time, he decided against it.
And thus Mirio ended up on his hands and knees, gagged, on all fours, his blue eyes covered by a blindfold. His long thick cock nested in a cock ring.
"So hard already?" He asks, running a single finger past the cage, to touch that hot hot skin. Mirio whines and writhes, but he doesn't move otherwise, keeping his position as ordered. His arms are tied behind his back; his face buried on soft fluffy pillows.
Tamaki smiles, running that single finger's nail up Mirio's skin: up his abs, to his sides, and then down his spine, to his ass.
Tamaki could write a book praising Mirio's ass. He could write hymns and poems about how round and perfect it is; how good it looks bruised up or scratched and how full and soft and good it feels between his fingers. He would give half of that book to that pinky, slutty little hole.
He kneads the flesh of his buttocks and spreads them. Mirio's breath hitches as he runs his tongue up his crack. He imagines how it feels: the cold and soft texture of his tongue so close to his balls and not there and then up, up up until it finds his hole. The ring of muscles is warm for his tongue and tight and sweet; a taste of that one flavored lube Tamaki doesn't hate. He moans in his ass, pleased, as if Mirio's ass was the tastiest thing he'd ever tasted.
He can feel Mirio's breath hitch; his voice co sighs and moans leaving his throat. He could eat Mirio's ass forever; just to see him quiver and shake like that. Just to feel it's him making Mirio feel that. But it's Mirio's birthday, and Tamaki has to do as he asked.
He doesn't dwell; prods Mirio's ass with his tongue for a little before pushing in one finger aside his tongue. His boyfriend writhes and hisses but otherwise stays still as Tamaki's tongue and fingers fuck him. Tamaki wonders if he can feel the way his own breath hitches when he moans, and shivers. If he knows how hard it is not to palm himself and come just from listening; just from seeing him.
He leaves two fingers inside him, moving in and out of his ass rhythmically. Then he kisses his way up Mirio's ass, complimenting him: how good he tastes, the tastiest little slut he's ever tasted.
Even Mirio's back goes red at that. Tamaki can't see his cock, but he's very sure he could have seen it throb inside its cock ring.
"Such a dirty, dirty little whore," he mutters, his tone low and soft and loving, "my dirty little whore."
Mirio whimpers, and nods, as Tamaki works yet another finger inside of him.
He can feel the expansion: can feel his body relax around Tamaki's finger and take him. His breath hitches. He's counting: four fingers nested inside his ass.
"You're so loose, slut," Tamaki whispers on his spine, almost thoughtfully, "you like this, don't you?"
He moves his hand, twisting his fingers and making him see stars. He's trying to avoid his prostate, but four fingers in, it's almost impossible.
"Maybe I should just keep you like this," Tamaki whispers, softly, twisting his fingers inside Mirio's ass, "to warm my hand, would you like that, slut?"
Mirio nods. Then he shakes his head. And then nods again. All the while he pushes on that hand, trying to get it to go deeper.
Pain flashes in his ass, the sound harsh and quick in the quiet night.
He knows Tamaki slapped his ass with his other hand. He has spanked him so many times by now he'd recognize his hands in his sleep. There's a sting in his ass, and it makes Mirio's cock throb.
"Stay still, slut," Tamaki warns him, softly, ever so patiently, "do you want me to spank you?"
For a tiny split of a second, Mirio considers moving: get his partner to bruise his ass black and blue. He knows he'd cry and beg, he knows the bruises would stay there for days, and that he'd have to stay back in his agency's locker room, waiting for everybody to leave before changing. The idea is tempting, wonderful, but then the hand in his ass moves, and Mirio doesn't want it gone. It feels good there. He feels so full. He doesn't want to lose that.
And so he shakes his head furiously, making Tamaki chuckle. Mirio can imagine his face; smiling gently, looking at him as if he held the moon and the stars in his hands.
"Pretty little whore," Tamaki coos, "you'll like the next part."
And with those words, Tamaki starts to move his fingers. Mirio can feel them move up in his ass, curving, touching every nerve. He whines and moans but otherwise stays perfectly still, not wanting to mess up his master's work. First, one finger closes in, and then another one, and another one, until his boyfriend is pushing a fist in and out of him. Mirio whines and pants, almost screams, and Tamaki keeps his fist there, perfectly still, so impossibly large, but in.
"Maybe I should record this for you?" Tamaki asks, taunting him, as he moves his fist inside his body, "so you can see how much of a slut you are, how about that?"
Mirio nods, then he shakes his head and then he nods again. His head feels fuzzy, his whole body burns, and his ass burns so good even with the lube. Tamaki's voice seems to come from very far; a stream of light in the turbulent waters of just feeling. When his fist moves, Mirio's toes curl. He moans, openly and so high-pitched and wantonly he can't recognize his own voice. He tries to push on that fist, get it to go faster, but Tamaki's other hand keeps him in place. He can only whine, and moan and sob and beg pleasepleaseplease-
"You take me so well- so loose for me, aren't you?"
Mirio mutters a "yes." It's wanton and slutty and quickly followed by more yes, please yesyesyes. Tamaki's voice seems to come from so far away. Mirio sobs and nods furiously, his wrists fighting against the restraints in his hands, his cock trapped in that cock cage. He can't move. He can't breathe. He needs to come. He has to come.
"Do you want to come on my hand- or on my cock?"
There's no malice in the question, no taunting. Tamaki's tone is sweet and soft and cooing. The hand that held Mirio's hips comes to pet the baby hairs at the base of his neck. Even with his hand in his ass and insults in his lips, Tamaki can be tender, soft. Mirio leans into the contact the best he can, craving it.
Tamaki's hand feels so good in him. Every tiny movement sends pleasure down his spine. It's so good.
His cock will feel even better.
"Y-your cock," he whispers, broken and tiny, but loud enough for Tamaki to hear him, "I want- I want your- ah."
Tamaki moves his fist again, sending sparks behind Mirio's eyelids. It feels so good that it hurts, and that hurt makes it all the better. Mirio feels his body on fire, lit up inside out. He sobs, and moans and whines, and begs. I need your cock. I need you. Please. Please pleaseplease-
Tamaki withdraws his hand ever so slowly, patiently, almost lovingly. Mirio can hear him coo at him and praise him, just a little more, a little closer, as he opens his hand, as he slowly, ever so slowly, withdraws it from his ass.
His hole is gaping, empty, when Tamaki finally withdraws his hand. Mirio can feel it twitch, closing on nothing.
He can hear Tamaki talking to him. Such a dirty slut, he says, so loose and gaping for me. He asks Mirio if he is ready, though Mirio knows, the true question is whether he is sure.
When Tamaki asked him what he wanted for his birthday, he didn't have to think about it hard. He's been mewling the thing for months; years, maybe, even if he would never tell anyone about it.
On the years they've been together, Tamaki has fucked him with all sorts of things — tentacles, many types of vegetables, and all kinds of toys and stuff. But Mirio always avoided asking for animal cocks; afraid of what it'd sound like, and the implications of wanting something like that to begin with, and what if Tamaki thought he was weird, or a pervert. Which he probably is, but it doesn't mean he wants Tamaki to think about him like that.
But he was underestimating him. Tamaki didn't even seem surprised. Immediately, he started to talk about logistics; how he'd have to stretch Mirio first, to make sure he wouldn't hurt him. Especially once Mirio added a little something to his request.
"I'll put it in now."
The first thing Mirio notices is the size. The horse cock is roughly the same width as Tamaki's fist, but longer. It's different from his usual cock: thick starting from the tip and so long it doesn't seem to end, it fills him up so much, so good Mirio's eyes roll back into his skull. He doesn't moan — there's no way he could make a sound even if he wanted to. A tiny, irrational part of him fears that it's too much; that cock will come out through his mouth.
It doesn't happen. He feels Tamaki's hipbones on his ass; the heavy slap of too-huge-to-be-his balls on his ass. There's a single hand on Mirio's hip that's firm and steady and secure, holding him together.
And the praise. My good little bitch, so full of me. You're taking me so good; so good for me. I'm going to breed you so good. Would you like that?
He knows it's a real question; he knows Tamaki won't move until he tells him to. Because it's the first time they do this, and he doesn't want to hurt him. But Mirio can't talk: every cell in his body is overwhelmed; every inch of his brain full of how full he is. Fuller than ever.
He feels Tamaki move — slowly, deliberately. Just the slightest little trust. He hears a strangled cry; like an animal in pain. And his throat hurts, so it was probably him.
Another thrust. Quicker this time. And Mirio can feel himself moan: every inch of his body buzzes and burns. He doesn't know up and down, or where he is, or who he is.
"You're- the dirtiest- ah prettiest- whore," oh, but he knows Tamaki; he knows his voice, soft and finally finally cut off by moans. He knows his praise, and his touch. He knows the hand that presses down his neck and keeps him in place as he fucks him harder.
Mirio screams, and moans. He's sobbing for sure, his throat constricted with sobs and more and yes and pleasepleaseplease-
He can feel when Tamaki is closer to come — his thrusts get shorter and quicker; more erratic. He's trying to work something in — a bundle of tissue even thicker than his manifested cock. It makes him whine as he takes it, so big and so overwhelming he could've missed Tamaki's bands — working the cock cage out, freeing his oversensitive cock.
Mirio cries and sobs and begs; his ass taking the knot in without pause, he can feel he tries to swallow it, closing on him like the tight ring of muscles a bitch would have.
The second his cock is free, Mirio starts coming — his toes curl, his body shivers and his eyes are well up with tears, and oh fuck he is coming and he can't finish; he keeps coming, his prostate relentlessly abused by that giant cock and fuckfuckfuck-
The knot pops. It's inside, locking them together. Mirio screams, and precise fingers work his cock in precise thrusts.
And then Tamaki is screaming, and coming inside of him.
His cum has nowhere to go: it just fills him, nearly collapsing his insides. He feels he's going to explode; his belly feels about to burst. He's so full, so so full. There's nothing but that; the feeling of sweat in his skin and Tamaki, hot wherever their skin touches, his fingers drawing long circles in Mirio's back. For a few blissful seconds, there's just him, so full of Tamaki he is about to burst.
He can't remember the world getting into focus. He can't remember moving, or Tamaki moving. He can remember the feeling of being empty all of a sudden, but not quite. He can remember the wet cloth over his thighs, cleaning the mess of cum off his skin, gently pressing the skin of his belly to get the cum out.
Then he is nested on Tamaki's chest, being carried around. And then they're both in the bathtub. There's a tiny, simple voice in his mind that feels awkward, hovering over Tamaki like an overgrown house cat, but Mirio can't feel it. It doesn't matter: Tamaki doesn't mind. He won't mind either.
He doesn't know when or how Tamaki changes the sheets. Where they even having sex on their bed?
It doesn't matter. Tamaki places him gently on their bed, and then lays down himself, bringing him to his chest. He runs a hand through Mirio's hair, humming a tune.
Mirio doesn't feel like talking. He doesn't think he could if he tried. And it's fine; they can do that in the morning.
A minute, or maybe an hour or two later, Mirio realizes which song Tamaki had been humming.
Happy birthday, to you, happy birthday to you.
Yeah, a really really happy birthday.