Mitsuba is a ghost who wants to become human again. He died on his mom's birthday while trying to get ingredients for a soup he wanted to cook for her. Kou is an exorcist who tries to be as good as his brother. Kou found Mitsuba at the lockers. Mitsuba looks at Kou. Mitsuba: "Do you remember me...?" he looks down, not expecting much. He was Kou's former classmate, but no one remembers him. Most of his old classmates can't even see him. Kou looks at Mitsuba and shakes his head Kou: "Sorry... I don't think I know you..."