A mysterious creature destroys 70 percent of this moon. The creature warns that when he is not crushed by March of this past year, Earth will be next. The creature demands that he becomes the homeroom teacher for 3rd tier e-class in Kunugigaoka Junior High School. The federal government is powerless to express . The creature then becomes the homeroom teacher of 3rd tier E group that consists of failed students including Nagisa Shiota (Ryosuke Yamada). The creature is known as Teacher Koro. Meanwhile, the government requests that the students try to kill Teacher Koro though he possesses powers. The government delivers a 10 billion yen reward for whom ever successfully kills him. The students are bemused by the circumstance, but decide to kill Teacher Koro. The students finds themselves using a fantastic time with their brand new educator, As soon as their class starts with freshman Koro.