Mikio is a 29-year-old P.E. teacher at Kisaragi Academy Senior High. He's responsible for physical education and gymnastics in the first grade classes. He is rude and, despite repeated sermons by the principal, doesn't seem to be improving. Under the pretence of acting strict, he treats and talks with prejudice when teaching the students. Although he's acting on his own educational philosophy based on forcing others to stay in line, it perpetuates a vicious circle which nobody accepts.