The film tells the story of an unknown creature who blew up 70% of the moon and threatened to destroy the earth in a year, serving as the mentor of Class E, the most unfavored class in the school, and his students. Although killing a teacher is a Mach-level creature with fast movement and strange tentacles, he tries his best to go through fire and water for his students. As a result, the classroom, which was filled with a strange atmosphere, has become an unforgettable memory of Class E for 3 years. On the other hand, the agreement guarded by the 3-year class E students and killing teachers with bondage and sincere interaction also accompanied them to the future 7 years later.