Nothing excites middle-schooler Kobayashi anymore. Except for his friend Hashiba, all other people are the same to him. His dull life became exciting when he woke up holding a weapon and found his homeroom teacher dismembered in the classroom. The investigators suspected him but Kobayashi was more than willing to cooperate. He was even cheerful about being part of a murder. Finally, his life was exciting. All he had to do after all was find the real murderer.