摩周 一穂

Teacher of 2-A and supervisor of discipline committee, is fear by most of students. Is a true sadist that gets sexually aroused by inflicting pain on others. Has a special ability to detect people that are consider naughty/bad or simply undisciplined/lazy/pathetic or any other perceived bad traits. The higher the rating the more she wants to discipline.

Her husband was a pathetic insecure rich person with no value other than money. After beating him long enough he became out standing person earning multiple degrees and becoming a very confident an successful/respected businessman. Which in turn Mashuu no longer loves him for not being pathetic. Which is also why she decided to become a teacher to discipline naughty students. Her physical beatings are some how able to generate some type of arousal claiming its because of her love. Which despite everyone being afraid no one has complained about her yet.

she is shinichi older sister