Picture of Korosensei (Koro Sensei)

Korosensei (殺せんせー korosensei) is the homeroom teacher for class 3-E of Kunugigaoka Junior High School, and the main antihero of Assassination Classroom. He is responsible for gouging out a large chunk of the moon, making it a permanent crescent moon. As if it's not adequate; he plans to destroy the earth after "teaching" class 3-E for a year.