Otokojuku
Otokojuku (男塾, Man Private School?) is a private boy's school in Tokyo, established over 300 years ago. The headmaster Heihachi Edajima gathers delinquents from all over Japan and trains them to become the leaders of the next generation.
Amongst the students, the first years are viewed as slaves, the second years as oni, and the third years as Enma. The third years take instruction from the headmaster alone, as the rest of the instructors are not at the same level as them and can not outpower them enough to punish them. The third years run things from the Tendo Shirne (天動宮?), and will tour all over Japan in order to settle disputes.
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