S1·E75 SOLITUDE (episode)

When class 2-D's Shuuichi Morita loses control, Kiri's action makes him throw the chair towards Mimori. Sasuke tells Kiri to cooperate, but Kiri refuses to follow Sasuke's orders. Later, Himeko hangs out with Kiri who shares his story about Kihara who was a victim of Kutsuwa, a teacher from his old middle school. When Kiri's old teacher comes back to Kaimei High School and bullies Himeko, Kiri Kato loses his composure.