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Tadashi lay on his bed, one hand down his pants, the other absently working over his chest. His cheeks dusted a rosey pink, rubbing against his pillow as he squirms on top of the sheets.
Hiro had come home not ten minutes ago, sneaking in through the garage so his brother wouldn't suspect he had been bot fighting again. After he'd put everything away, the house had been eerily quiet as he made his way upstairs. Aunt Cass was out for the evening, and Tadashi was usually already home from school at this time. His suspicions were confirmed when a muffled groan resonated through the silent hall.
There was no mistaking who the voice belonged to, Hiro had heard every noise his brother had to offer, but this was something different. The tone of it, the way it sounded so needy, so desperate. Did Tadashi have someone over? Hiro's cheeks immediately darkened at the idea, but the door to their room was cracked and his brother wasn't the type to be so open. Slowly Hiro moved closer, concealed enough in the dark hallway as to not draw attention to himself while he peaked inside.
The sight was mesmerizing.
Hiro was no stranger to masturbation, he wasn't even a stranger to seeing other people masturbate. As a fully functioning 14 year old boy, he was well aware of his sexual urges, and there definitely wasn't any shortage of porn on the internet. Although, this wasn't porn, this was 100% the real deal and Hiro's body was reacting faster than it ever had before. There was something about the way Tadashi was splayed across his bed, hand leisurely fisting his cock that had Hiro's pants tightening at record speed. He tried to reason with himself that it was just the act, not the way his brother's eyelashes fluttered over high cheekbones, just the idea of it all, instead of the soft pants coming out in Tadashi's deep voice.
Not that Hiro thought his brother was unappealing, not in the slightest. He knew that many people thought Tadashi was attractive. He had a nice face, with feathery black hair and warm eyes. He was tall and fit and so genuinely nice it drew people like moths to a flame. He was everything Hiro wasn't, and people loved him for it. The only downside Hiro could think of was that he was a huge nerd, and nerds didn't typically have time for relationships, or so his brother told him.
As Hiro got lost in his head, Tadashi picked up the pace. His hips began to thrust with more purpose, fist tightening around the swollen head of his cock before dragging back down the shaft. The pace looked excruciatingly slow to Hiro, who preferred a faster, more sloppy approach. Everything about his brother screamed precision. A squeeze here, a flick of the wrist there, the slow determined speed at which he worked himself over. It was so Tadashi, Hiro almost wanted to roll his eyes.
Hiro's cock bulged against his shorts, drawing his attention back to himself. Arousal was pulsing through his body in little electric waves down his spine. He wanted so badly to just drop his pants and jerk off in the hallway, but there was no telling when Aunt Cass would be home, and Tadashi would most likely finish before he did. He settled for palming himself through his shorts just enough to relieve the pressure while he watched.
Tadashi's eyes were closed, lids fluttering passionately. He was biting his lip to stay quiet, but it wasn't enough to keep the tiny noises from floating out to Hiro. He had never seen his brother look so provocative, with his cheeks flushed and back arching wantonly of the bed. It was something he never realised he wanted until now. Tadashi had never been a sexual being to Hiro, he'd always been the helpful, supportive older brother, and nothing more. Now observing him like this, Hiro wonders if he'll ever see him that way again.
Fist starting to falter, Tadashi releases with a small shout, covering his torso with thick white ropes of cum.
"Hiro, Hiro, oh fuck, Hiro..."
Hiro's eyes shoot wide open, hand flying to cover his obvious hard on afraid he'd been caught. But no, Tadashi is still stroking himself down, eyes clenched tightly. It was whispered like a prayer, like a secret that was meant for no one but himself. Realization hits Hiro like a brick to the head. Of course he hadn't been found out, the tone was all off.
Tadashi had been fantasizing about him. Tadashi had been imagining he was doing something with Hiro. He was getting off thinking about his baby brother. And fuck if that wasn't the hottest thing Hiro had ever seen.
There was no way he could stay in the hallway after that, he was half wild with arousal, eyes cloudy with lust. He ends up back in the garage, jerking wildly over a trashcan. Tadashi's voice is playing on a reel in his mind, driving him closer and closer. He imagines warm palms ghosting over his sides, pinning him down. The vibration of a deep chuckle reverberating through his chest, his back. Tadashi would be so gentle with him, he always has been, and Hiro is driving himself wild thinking about how it would feel to be full with his brother's cock, and suddenly he's coming harder than he ever has before.
By some miracle he manages to shoot it all in the trashcan despite having his eyes closed, slumping against one of the cluttered shelves as he tries to keep his knees from giving out.
"Hiro?" Tadashi must have heard something then, Hiro quickly cleans as best he can and tries not to panic when he hears his brother's heavy footsteps thud above him.
"You okay down there?" He tries not to groan in embarrassment, and is quick to reassure his brother.
"Yeah, just dropped something! Be up in a second!" That seems to be good enough, and this time Hiro actually does groan out loud, dreading having to look his brother in the eye after whatever the hell that was. He has no idea what he's going to do from here.
For once his brain is completely blank.