Kai Chisaki, also known as Overhaul, is a major antagonist in the anime series Boku no Hero Academia. He is the leader of the Shie Hassaikai, a yakuza organization, and possesses a Quirk that allows him to disassemble and reassemble anything he touches. Overhaul is a meticulous and germaphobic individual, obsessed with restoring the yakuza's former glory. His calm demeanor and ruthless nature make him a formidable foe. Throughout the series, Overhaul is primarily known for his role in the Shie Hassaikai arc, where he clashes with the protagonist, Izuku Midoriya, and other heroes.