A demon lord's kid has to pass as a hero student while everyone at school is actively hunting demons, and the show treats this like a sitcom where the joke is never that he's a demon, it's that nobody can tell. The comedy lives in Yu Renjie's deadpan survival instinct colliding with actual friendships he didn't plan on forming. By episode three you stop rooting for him to succeed at the con and start rooting for him to not have to choose between the con and the people he's stuck with.
Yu Renjie walks into Hero's Academy with a single mission: earn a legitimate credential for his demon clan and survive long enough to leave. His father sent him undercover, gambling that no one would suspect the dark lord's own son of infiltrating the institution dedicated to hunting creatures like him. The plan is simple. Blend in. Graduate. Get out. Then his cover gets blown on day one. With righteous knights patrolling every hallway ready to execute any demon they find, Yu has exactly one option to stay alive: transform his appearance completely. Dressed as a girl and armed with nothing but quick thinking and sheer nerve, he navigates the absurd social minefield of academy life alongside genuinely heroic students who have no idea they're befriending their sworn enemy. Every class is a performance. Every friendship is a tightrope walk. Every moment threatens exposure, yet somehow the ridiculous situations keep piling up faster than he can contain them. His dangerous secret collides with genuine connection in ways neither side expected.