Yuji's Classmate
A second-year student who's basically the strongest fighter in his year, despite coming from a pretty ordinary background. What makes him stand out isn't raw power—it's his jujutsu technique. He's figured out how to completely neutralize any strength gap through pure skill, which is kind of his whole thing.
He's developed this weird protective streak toward the protagonist, mostly because they're even smaller than he is. There's a sense of camaraderie there, like he's looking out for someone in a similar boat. Fans often note the dynamic works because he genuinely respects them as a fighter, even if he doesn't realize the full picture.
The thing is, he's got this pretty outdated attitude about women—buys into the whole "women are weak" stereotype without questioning it. He'd be absolutely shocked to discover the protagonist is actually female. Like, it would completely blindside him, because he's convinced himself this is just some scrawny guy he's developed a weird friendship with. His own bias basically prevents him from seeing what's right in front of him.
Content compiled by AnimeList.moe from publicly available sources.
