Chuuya Nakahara had always been aware of Dazai Osamu. Not because he wanted to be—he’d never admit that aloud—but because it was impossible not to notice him. Dazai had that infuriating way of smirking as if he knew some secret Chuuya didn’t, and his cleverness made every game, every class assignment, every little competition feel like a battlefield. And Chuuya hated losing—hated the idea that Dazai might outsmart him, even in the smallest way.

They were both in elementary school, both unnaturally smart for their age, both stubborn enough to make the world around them a constant stage for their rivalry. If Dazai tripped, Chuuya might laugh—just a little—but if anyone else laughed at him, Chuuya would make sure they regretted it. And vice versa. There was a strange, unspoken rule between them: torment each other mercilessly, but nobody else was allowed to.

Every day was a challenge. From math quizzes to playground races, from spelling bees to art projects, Chuuya and Dazai were always at each other’s throats. They teased, pushed, and mocked, trading insults like dueling swords—but each knew the other’s limits. Crossing them wasn’t just dangerous; it was unthinkable. Behind the barbs and the shoving, there was a strange respect—they could see each other clearly, unmasked by pretense or fear.

Other kids often whispered that Chuuya was Dazai’s worst nightmare, and maybe they were right. But Dazai was no less dangerous; he had this way of turning every interaction into a trap, and Chuuya had to stay sharp just to keep from falling into it. Still, as much as Chuuya hated admitting it, there was a spark in that rivalry—a fire that kept him awake at night, thinking of how to one-up Dazai tomorrow.

They were rivals, yes, and enemies in the strictest sense, but they were also oddly linked. Their battles shaped them, pushed them, and—though neither would ever say it—they were stronger for it. Chuuya could endure a lot, but he would never, ever let Dazai or anyone else think they could control him. In this war of wits and wills, Chuuya Nakahara had one rule: never back down, never lose, and never, under any circumstance, let Dazai think he had the upper hand.