Puberty sucked, Kaoru decided.

His voice was going nuts, his hormones were going God knows where, he was paying more and more attention to his brother's body – he was sure that he wasn't supposed to – and Sex Ed. had become torture.

"So. Who can tell me what the prostate gland is?"

Did they have to have naked plastic models up the front? Well, they probably did, but did they have to be so realistic?

With a groan, the younger twin let his head fall onto the desk. Hikaru looked at him from his own seat and frowned. Kaoru'd been confusing him for a month now, with his blushing and stammering excuses, before running off to the bathroom.

And locking the door.

They didn't lock doors. It was an unspoken rule. But Kaoru was breaking that rule every day, rushing off to his room – not Hikaru's – and not coming out until it was time for dinner.

Noticing that his little brother was shifting uncomfortably in his seat, Hikaru rose from his chair, glared at the rest of the class, grabbed Kaoru's arm and dragged him from his desk to the door.

The teacher didn't bother to ask where they were going. He wouldn't've gotten a decent reply, anyway.

Kaoru winced as his too-tight pants rubbed against his groin, the nerves there sending messages to his brain along the lines of; "BDKSHDKSABOENXKDOKLW FUCK FUCK FUCK OW FUCK OW OW OW OW."

"Ah, Hikaru, please let go." He choked out, not being able to stand being dragged around any longer. His older twin ignored him and he let out a whimper, his eyes beginning to tear up at the pain.

They didn't stop until they reached one of the bathrooms, and even then it was only for a second. Once Hikaru had flung open the door and made sure Kaoru was safely inside – meaning that no limbs were liable to be cut off – he swung it shut and bolted it from the inside.

In the few seconds in had taken him to do that, Kaoru had crawled into a cupboard.

The brothers fought for a bit over the cupboard door, one wanting to shut it and the other wanting to keep it open. It was only when Hikaru's hand slipped onto Kaoru's lap that the younger let go, sending the door – and his brother – flying.

"Ah – Sorry, Hikaru!"
"Kaoru." The aforementioned older twin growled, holding his nose where the flying door had hit it.
"What the Hell is wrong with you? Stop doing whatever it is you're doing and talk to me, dammit! We're supposed to share things, aren't we? Why the Hell aren't you acting like you used to? You're the one who's always telling me that whatever happens to one of us happens to both, aren't you? So then why the Hell aren't you sticking to that?"

Hikaru's tirade would've continued, if Kaoru hadn't suddenly dropped his head to his chest and groaned. From where he was sitting, he could see that his little brother had at least one of his hands curled into a fist, and the concern that had been nagging at him for weeks overpowered any misdirected anger he had. Forgetting about his nose – it wasn't even bleeding –, he crawled the few centimeters he had been knocked back to the cupboard, and the closer he got, the clearer Kaoru's ragged breathing got. Eyes wide, thinking that he'd made his brother cry, Hikaru flung himself to cover the remaining space, arms wrapping themselves tightly around Kaoru's chest. Immediately after he did this, Kaoru's head shot up, and he stared at his brother before swallowing thickly and twisting his body to bury his face in Hikaru's neck.

"K-Kaoru?" To say that the younger's actions had surprised him would be an understatement. As he was just considering moving his arms away, Kaoru's hands latched onto his elbows and his teeth bit down on his neck. With a yelp at the sudden pain, Hikaru's body automatically began to try to get away from the things that were sending the signals to his brain.

It stopped when Hikaru realized what his brother was doing, and regained control of his senses.

Kaoru was humping his leg.

…He was also moaning quietly, but Hikaru could only process one fact at a time.

After a few seconds, the true realization of what was happening hit him.

Kaoru had one of those – what had the teacher called it? – erections. They were supposed to be when the hormones or whatever decided that the body wanted pleasure, and pressure against the penis gave that pleasure.

…So that was why Kaoru had been sneaking off so much.

Hikaru released his hold on his brother and gently pushed him away, eyes widening as they took in the sight of Kaoru's face. His cheeks were pink, his eyes were shut and his mouth was open, gasping for air.

It was enough to make Hikaru's blood rush down to his own penis.

"S-sorry." Kaoru panted, his nails still digging into his brother's elbows.

"Kaoru?" Hikaru asked slowly and deliberately, raising a hand to brush his twin's fringe away from his face.

"Why didn't you tell me?" All he got as an answer was a needy whimper. Hesitantly, he moved the hand that had pushed Kaoru's fringe away down his twin's body, stopping to cup the unmistakable bulge in the young teen's pants. He wasn't too surprised when Kaoru let out a shuddering moan, and when his head fell back down to rest against the older twin's neck.

Still cautious, Hikaru began to rub the bulge, his twin's reactions egging him on, until he had enough confidence to carefully undo the buttons on Kaoru's uniform and reach inside for what he knew was waiting.

He wasn't disappointed by the choked gasp Kaoru gave when his fingers wrapped around the pulsing flesh, nor by the way his brother began bucking into his hand desperately.

Hikaru felt his own hardening penis twitch in response, and without thinking about it, he used his free hand to undo his own pants, gently pulling out his erection without a second thought.

He did the same for Kaoru, and both twins shuddered with pleasure as their erections came into contact, the younger's already lubricated with pre-come.

Kaoru had begun biting Hikaru's neck again, using the skin to muffle his cries. Now on automatic, the elder's hands grasped his twin's hips and ground them against his, both their penises being rubbed against flesh on all sides.

With a muffled cry of his brother's name, Kaoru came, warm spurts of his semen covering both of their groins and lower stomachs. Unable to bear the new pleasure assaulting his senses, Hikaru followed soon after, groaning as his hips bucked a few last times before he lay still, his muscles twitching every so often.

Kaoru finally released his brother's skin, but didn't move his head. He just lay there, on top of Hikaru, panting and trying not to fall asleep.

He lost that particular battle once his brother's breathing evened out and his heart began to beat the way it did when they slept.

Two hours later, an irritated Kyouya and an excited Tamaki were touring the bathrooms.

Just take a guess at what they found once Tamaki broke down the door.