Oono

大野

He served as Karma Akabane's instructor during the latter's second year at Kunugigaoka Junior High School.
Like the other main building staff at Kunugigaoka Junior High School, Oono is highly discriminatory and openly hostile toward the students of Class 3-E. He is a contemptuous individual who frequently looks down on those he deems inferior. He is also detestable, as shown when he deliberately disrupts the concentration of Class 3-E's students during midterm exams.
Oono is intensely concerned with how others regard him. He was initially fond of Karma Akabane due to his good grades, but later abandons him when he believes Karma is harming his reputation.