Affectionately referred to as "Mu" by her classmates, Mutsumi Mutsu is presumed to have supernatural powers that allow her to make contact with heaven, hell, and dead people. In addition to this, she supposedly has the ability to erect barriers to protect herself and classmates from otherworldly spirits and forces. No student dares to stand against her out of fear of incurring her wrath. Like thus, Mutsumi Mutsu becomes queen of the classroom.