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Riku is a bad person for doing this. There must be some place in Hell that Dante talks about in the Divine Comedy, some circle of hell dedicated to the unfaithful. He's pretty certain that's the case, but he can't remember correctly what's the punishment when Sion calls him.
If Riku were a better person, he'd sit down at the table in his apartment with his boyfriend of three years, Daeyoung, and tell him the whole truth.
He would tell him that half a year ago, when Riku went out to a bar with his friends to have fun and without raising suspicion, he ended up kissing a tall blond guy in the darkest corner of the place, a guy he hadn't met until that night.
It was supposed to be just that, a mistake caused by alcohol. A bad judgment. Riku only did it out of spite. He was angry with his boyfriend for something he doesn't even remember now, and he was never supposed to see Sion again.
But that quickly changed. A week later, he ran into Sion at the gym and tried to pretend he didn't know him, but before Riku knew it, he was kneeling in front of Sion as he pulled down his pants in the gym shower.
He started running into Sion on the street, at the gym, in bars, and everywhere, and each time they ended up hiding in a corner, with their lips swollen and their pants down.
The first time was a mistake, the second a slip, the third, there was no excuse.
(The third time it happened, it wasn't as casual as the previous ones; Sion sent him a message on Instagram, just a time and an address: 6:30, his place. When Riku was getting dressed again to go back home, he told Sion "I have a boyfriend that I love, we have to stop meeting like this, I don't want any trouble" and the only response he got was "I can share". Riku would be lying if he said that didn't seem hot.)
Riku loves his boyfriend, he swears he does. There's nothing wrong with Daeyoung, who cares for him, loves him, and respects him. He can't compare him to Sion, who, up until now, hasn't shown anything more than physical attraction to him.
This isn't a forbidden romance or anything like that; it's a carnal matter. To Riku, it's the adrenaline rushing through his veins when Sion texts him "My place, 6:30," and Riku makes up an excuse that Daeyoung never doubts.
Riku is a bad boyfriend, but Sion isn't much better. While for Riku it's all about the adrenaline rush of lying, for Sion it's about Riku being someone else's. Riku is sure that if he breaks up with Daeyoung tomorrow, Sion wouldn't hesitate to end things with him. It turns him on that Riku is someone else's property, knowing that he can't leave marks or anything that could be evidence of their encounters. Sion would say things like "Can your boyfriend fuck you like me? I don't think so", knowing it to be true.
But Riku also likes thinking about his sweet, loving Daeyoung, waiting for him in the apartment they share, making dinner, while Riku is bouncing on the cock of a man he knows more naked than with clothes on, moaning over and over, "You're so much better, so good."
Riku isn't a good person. He never claimed to be one before, and he can't do it now.
At times, when he goes on dates with Daeyoung and they watch movies before bed, at family dinners and birthday parties, Riku can't help but feel guilty for breaking his trust. But it only lasts for a second, and before he realizes it, he's standing in front of Sion's building, waiting for the door to be opened.
His friends —the few who know about this affair— will say that he should leave Daeyoung if he wants to fuck someone else so much, but they don't understand: it's hard to regret it when the sex is this good.
Because Sion is so good.
Sion always leaves him sore, in a sexual haze; it's an extra-sensory experience to have sex with him. Riku's mind stops belonging to his body when Sion fills him.
Like now, as Sion keeps him on his knees and elbows, his back arched like a cat, presenting himself to him like he belongs to him, and he probably does, because Riku keeps coming back.
"Look at you, all dumb for it." Sion's fingers tangle in the roots of his hair and he tugs, forcing Riku to look in the mirror. Sion is right. Riku is dumbfounded by it—by him, all sweaty with glassy eyes and labored breathing. He doesn't put any obstacles in the way of the screams escaping his throat as he pushes his hips further and further back to meet Sion's.
Sion's cock isn't extremely long, but it's definitely thick. It stretches him so much that Riku remembers it all day after their encounters. He screams when he enters him and begs for more when Sion stops. This is what it feels like to be hate-fucked, he thought the first time. After a few times, Riku soon realized that's how it feels every time.
Sion is mean to Riku, and Riku enjoys it, too used to the gentle ways of his boyfriend, who could never even try to treat him rough.
Daeyoung is sweet and loving, and Riku enjoys it. He feels incredibly sexy, and loved, having sex with his boyfriend. But Daeyoung could never blow him away like a piece of paper and use his body like a fleshlight as Sion does.
"You're a little slut, aren't you?" he repeats, and Riku can't do anything but try to form words that aren't pitiful moans, but he can't. "You like the way I fill you up, don't you? Much more than when your boyfriend does it?" It's a question, but there's no such doubt.
Sion fills him completely every time. Two months ago, they stopped using a condom just so Riku can feel the warmth of his cum dripping from his hole when they finish. So it can drip between his thighs when he walks to the bathroom, and so he can feel the rush of cleaning himself when he gets home, before Daeyoung notices it.
Sion's thrusts are rhythmic and hurried, he pounds with all his intensity, one of his hands still pulling Riku's hair and the other holding his waist with more force than necessary. The heat that takes over his body is inexplicable as Riku looks at his own reflection, his body being mistreated in ways that, before Sion showed up, he'd never even imagined. It's hot, it's so hot the way Sion takes over his body like he belongs to him.
Riku is numb, his body burning and aching at every thrust. He stays firm in his position only because Sion holds him there. Riku looks through the mirror at Sion's strong, sweaty, and defined abdomen that ends in a slight V, right where it hits Riku's ass. The sound of clapping echoing in the room is absurdly loud, Sion's neighbors must be complaining, especially because Riku won't stop screaming.
"Oh, God— yes, fuck, fuck, fuck, yes, yes" Riku doesn't think he knows any other words at this moment when his eyes roll back, he parts his legs even more and lets his chest hit the mattress, and at this angle, Sion stretches him out even further.
Riku doesn't think he'll ever want to stop; Sion always holds him firmly and pulls on his hair and nothing else, no marks, he'd said once and he'd never broken that rule.
"You're so tight," Sion tells him, his voice raspy, deep, and low. The growing knot in his stomach becomes biggers just from the sound of his voice.
Sion suddenly lets go of his hair, his face buried in the sheets, and Riku can feel the drool dripping from his mouth, wetting his face and sheets. His cock, which hasn't been touched since they started, drips precum onto the fabric.
This is the closest he'll ever get to being high on cock. It can't get any better than this, Riku can't hold out any longer. His back aches from the position, he can't breathe properly, even his nipples ache from how much Sion bites and pinches them.
"I can't," Riku says, his voice raspy from all the moaning and whining. He doesn't know how to formulate words when Sion's cock continues to open him up mercilessly. His whole body burns, and he feels alienated away from his own body. He can barely focus his eyes when he looks over his back.
Sion isn't even looking at his face, focused exclusively on the spot where his cock disappears.
"Yes, you can, princess, keep going," Sion says. He holds both of his hips and, while he keeps still in place, moves his body in order to fuck Riku, making him do all the work, rocking him on his cock. Sion isn't as affected as Riku, who cant even breathe, but he still moans at the sky, looking for air "Come on, cutie. Tell me what you want."
It's incredible how Sion pulls on one of his arms, limp at his side, holding him firmly behind Riku's back. He practically moves his body at his own whim, not really thinking about what Riku wants.
Riku would never let Daeyoung have control.
But he gives Sion all the power that he wants.
"Sion, hyung," Riku's in the middle of a fever dream, as is Sion. Sion moans in response and spreads himself across his back, covering him completely. It should be disgusting; the smell of sex in the room, their sweaty skin sticking to each other, like the sloshing of his hole never diminishing. It's dirty, and messy, and reckless, and Riku wants it all the time. He keeps calling Sion for a reason.
"Come on, princess," his voice hits Riku's ear directly, sending shivers down his entire body. He wishes he could stand up, hold on to something to change position, and yet all he can do when he raises his head is to look at himself in the mirror. He can see his butt, red from the blows; he sees his body and Sion covered in sweat, and he also sees his own face, completely gone. "Say what you want."
Riku's dick is red, hanging heavy between his legs, precum dripping from the tip. It's akin to torture at this point. He wants to cum so badly.
"I want to come." His voice doesn't even sound like his as he lets those words out. He can hear Sion's smile spread as he says affirmative words that Riku can't quite grasp. Sion has moved away from his back, holding his head by the chin and neck, forcing him to look at himself in the mirror as he picks up the pace.
Riku should have been more specific, but he can't bring himself to regret it when he hears Sion's balls slap against his own. It's completely obscene, it always is. Riku is too close, his body trembling unsteadily, and he could have started crying without realizing it.
He can see Sion's proud face as he pounds all of his walls. The pace is relentless and doesn't stop for a single second. Sion doesn't even check on Riku's comfort, keeping him in an awkward position where Riku can feel how his blood is having difficulty reaching his brain because of the grip on his neck. Sion to pulls him forward into an even deeper thrust, if that's even possible.
Everything is getting blurry as the pressure in his belly becomes unbearable, and all it takes is a small touch to his abandoned penis for him to cum. It's kind of pathetic the way he cums just from a cursory touch of his dick, but no one can blame him when Sion brings him to the brink with just his cock.
It's an explosion from his brain to his entire body, or vice versa, or simultaneously; it's hard to tell when his entire body collapses like a dead weight onto the stained sheets. His body burns everywhere and he can't feel his thighs, but it only takes him three seconds to realize he's moving, or rather, that he's being moved.
Sion flips him over and lifts one of his legs up to his shoulder, keeping him open. Sion keeps thrusting in, again and again, without stopping, keeping Riku's elevated leg in place. He can feel tears starting to form in his eyes from the overstimulation.
Riku's body burns even more than when he was a second away from cumming; he can feel his thighs cramping from the position and he can't stop squirming and whimpering as Sion continues to penetrate him.
Suddenly, Sion's cock is too big, too uncomfortable. He stretches him to the point where it's painful but Riku takes it anyway. He tries to breathe deeply as Sion's rhythm becomes sloppy and all over the place. Tears begin to spill down his face before he can stop them, caused from the mixture of pain and pleasure. Before he can realize it, Sion spills all of his hot, thick seed inside him, filling him.
They remain in that exact position, catching their breath for a few minutes, and when Sion pulls out of Riku, he can not only hear the splashing but also feel the thick drops escaping from inside him, spilling down and coating his body.
Riku doesn't fall asleep, but he could have. Sion is still kind enough to give him light, clean kisses on the forehead, and heads to the bathroom without exchanging another word, leaving Riku alone in bed.
When Sion gets out of the shower, Riku comes in. He quickly cleans his skin and hair to remove the unpleasant smell of sex that lingers on his body. He uses Sion's hairdryer so it doesn't come home wet.
And when he leaves the bathroom, Sion hands him a sandwich that Riku doesn't bother to ask what it's of.
It's almost a routine: he arrives at Sion's place, they do what they have to do and he leaves, without feelings involved, without making things complicated.
"See you," Riku says, and before he can hear an answer, he leaves the apartment. Once in the elevator, he takes his phone out of his pocket.
riku:
hey babe
im coming home, can we eat chinese food?
daeng:
sure my love
see you at home
riku:
love you
Three days later, Daeyoung asks Riku to marry him, and he accepts. He even makes this sweet Instagram post of their hands showing their ring fingers (a post that Sion liked that same day).
Four days later, he meets Sion again, who forces him to suck on the finger where the ring rests while cumming inside him.
Riku is a bad boyfriend. Probably a bad person too. There must be a place for guys like him in hell, those guys who give to charity and are hard workers, but continue to cheat on their boyfriends for months.
But who can blame him? Sion is too good to stop.