Yoru: is the villainous tritagonist of the Academy Saga. She is the War Devil who embodies the fear of war and conflict. She is a member of the Four Horsemen, who now occupies Asa Mitaka's body as a Fiend Asa Mitaka: is the main protagonist of the Academy Saga. She is a high school student who became the host of the War Devil Yoru, making her the inhabitance of the War Fiend though she still retains her human personality when Yoru allows her control, making her a rare case of a living Fiend host