The world's most famous and terrifying gangster family is on the verge of dissolution once the mysterious secret of Kikunosuke, the third and most powerful member of the Abashiri, is revealed. However, the Abashiri family's nearly peaceful existence becomes complicated when Kikunosuke enrolls in one of the most prestigious elite schools. There, rather than studying art and culture, students are forced to learn the most dangerous techniques for fighting and murder under the tutelage of cruel, psychopathic teachers. Only a handful of students manage to survive this hellish institution... but naturally, in this instance, the new student is the most terrifying member of the Abashiri, and things will never be the same.