Akira Kongou, the "Diamond Delinquent," transfers to Shiritsu Raimei High School. Despite his insistence that he is not a banchou (a Japanese student delinquent and gang leader), he quickly climbs the ranks of Shiritsu Raimei's gang until he becomes its leader. Akira now participates in schoolyard battles against bullies and punks from the twenty-three neighboring schools.