Toraji is the leader of the delinquents group enrolled in a certain school. That technical high school, full of Yankees, is divided into two gangs, “Toraji gang” and “Ryuuichi gang”, and they fight ruthlessly day after day. Today too, an one-on-one fight was arranged to decide who’s gonna be the real leader, but… Suddenly, Toraji’s father decided to come out and announced that he just re-married. After a brief moment of shock, Toraji realized his father’s partner’s son is his opponent, Ryuuichi…?! Now the two rivals end up under one roof… Who’s gonna be who?