"How should the existence of Ayanokoji Kiyotaka and the White Room be viewed into the future?" That decision will be made by Ayanokoji Atsuomi. Yet, the unexpected disaster of the moon breaking down was unprecedented. As well as the 10 billion Yen bounty that came along with it. "Whoever kills this monster will receive 10 billion Yen." The monster could move in Mach 20, and it was completely impossible to catch him off guard. They tried fighter jets, armies, everything. Yet it didn't work. However, for some reason, the monster insisted on teaching in Kunigaoka Junior High School. Class 3-E particularly, which was known as the End Class. A class of mischiefs, a class of failures. The government had no other choice but to accept, lending the fate of the world to the hands of a bunch of Junior High School children. Inside the assassination classroom. "You will enroll in Class 3-E, and kill the monster." Such were the words of Ayanokoji Kiyotaka's father, whose motive now was to make his son leader of Japan by taking advantage of this. He was given a mission as the best product of the White Room, like a machine designed to accomplish a task. If the class fails to kill him before graduation, the Earth will be destroyed. If they do kill him... then... How would the perfect, yet broken product of the White Room feel about it?