Chapter Text
Rantaro stood in the kitchen, yawning to himself as he cleaned up the mess he made while making dinner for his wife's family. He tended to come over with Sachie (his wife) a lot, whether it was just to visit or to stay a couple of nights. He got to know her parents very well, easily winning them over with the fact that he's a head chef at a Two Michelin Star restaurant. In other words: he was loaded.
Despite his wealth, he tended to dress casually and didn't like talking about money- at all. In fact, he preferred the cheap stuff. Except when it came to food, obviously. Her brother on the other hand, he didn't know much about. He knew that he was in high school, and that he liked Danganronpa, but not much more than that. Anytime he tried to approach the teenager he always seemed to back away, almost as if he was scared of him.
It was a little disheartening, but he didn't let himself take it to heart— he was far older than Kokichi, so it must've been awkward for him. Nevertheless, though, he always made sure to include the teen in what he did, asking him to help with dinner, or go with him to the grocery store— all of which he nervously declined. He couldn’t help but think about it as he got ready for bed, Sachie sleeping in a different room with her little sister. He smiled at the thought of them together— Sachie was so sweet with her, and the little one, Amane, was just as precious.
He finished brushing his teeth, slipping out of the day’s clothes and getting into bed, wearing nothing but his boxers.
Kokichi didn't know what'd gotten into him. Ever since he'd first met his sister's husband a couple years ago at their wedding, he couldn't stop imagining.. things. And he felt so bad about it, too, often not having the heart to talk to Rantaro because of it. It'd gotten to the point where he'd have reoccurring wet dreams about the man, often waking up with wet underwear and having to blow off steam with the vibrating dildo he'd bought in secrecy.
Tonight was one of those nights.
He'd woken up a couple of minutes before, now sitting on his bed with the dildo up his cunt and fingers desperately rubbing at his clit. He was so glad to have a vagina then, assuming that Rantaro was straight. Maybe he'd love how tight he was, how round his ass and thighs were, and how big his chest was, despite being slim.
"Onii-san~" he moaned, imagining the older man fucking into him instead of the silicone dildo. He tried to be quiet, not entirely sure who was awake and who wasn't. But he couldn't help but let out a couple of loud whimpers and pleas, desperate for his release. Meanwhile, Rantaro was just settling in, turning on the fan and getting under the covers of the queen size bed. He heard a strange noise from the room next to his, almost a whimpering; was Kokichi crying?
He thought about what to do; He could go in there and possibly embarrass Kokichi, making him dislike Rantaro even more, or maybe just ask him how he was doing in the morning— a check-up. He decided guiltily to go for the latter, settling himself back into bed and closing his eyes, soon drifting off to sleep.
After ten minutes of failed attempts at drawing an orgasm out of himself, Kokichi’s mind came up with a horrible idea. He knew it was wrong, and god Rantaro would probably hate him for doing it, but he needed it.
Quickly, he climbed off of the dildo and went over to his closet, not bothering to put the sex toy away. He quickly slipped a robe over his shoulders, not wanting someone to see his naked body accidentally. Then, he left his room and quietly walked to the one to the right of his, peaking inside and noticing the man he'd been imagining asleep, and alone. His legs trembled as he walked into the bedroom and over to where Rantaro lay, pulling the cover off of him. He quietly climbed on top of him and sat down on his lap, starting to grind down onto his boxers instantly. "I wish I could do this while you were awake.." he mumbled, letting out a soft moan of desperation. "I need you-..."
He felt tears form in his eyes, realizing just how jealous he was of his own sister. Rantaro made a few grunts in his sleep, his unconscious body bothered by the new stimuli, and as Kokichi’s pace continued, a bulge grew in the older man’s boxers, soon growing wet from Kokichi’s cunt. The younger lifted himself up just a bit, staring down at the bulge with an intrigued expression. His hands traveled down to the hem of his boxers, pulling them down quickly and watching as the man's dick sprung into the air, slapping against his thigh.
"Onii-san." He whispered, seeing if he'd wake up. When he showed no signs of doing so, he took a deep breath and slowly lowered himself down, having to cover his mouth to stop from making a loud noise.
"Haah-..." he moaned softly once he sunk the whole way down, his hand returning to his clit and starting to rub himself again. "You're so much bigger than my toy-" he whispered, feeling himself get close to his orgasm again. Right before he peaked over the edge he stopped his hand, instead starting to ride the one he was currently sitting on. "I wonder who you're dreaming of.. probably my sister." He pouted, wishing Rantaro loved him instead.
Meanwhile, the man began getting vocal, moaning softly when Kokichi sunk down onto him, taking him fully. Rantaro’s cock reached his cervix. It twitched inside of Kokichi, precum leaking onto his tight walls.
And Kokichi loved all of it. His eyes widened a bit at the moans, blushing darkly. He smiled, finding them cute.
"I love you-" he whispered, hand going back down to his clit as he leaned down so he was straddling the other. He contemplated leaving a hickey on Rantaro's neck, finally deciding to do it after about ten seconds. It was small and dark red, a perfect mark from him. His fingers moved faster after that, squirting a small amount (which got on the sheets) right before his orgasm peaked over the edge.
"Ngh- Fuck-!" He moaned, insides clamping down on Rantaro. The unconscious man gasped, soon cumming inside the boy as his hips involuntarily bucked. When Kokichi lifted off of him, his cock fell limp against his stomach, his boxers half way down his thighs.
Quickly, Kokichi got off of the bed, leaving a quick kiss on the man's cheek before he quietly rushed out of the room and into his own, covering his naked body up with his blanket and quickly falling asleep. His underwear, binder, and sleep shirt all lay on the ground beside his bed, along with the 6" green dildo and a bottle of lube. Rantaro on the other hand, he'd been left with his underwear down, sheets wet, and crotch soaked. All for him to awake to.