29-year-old Maehara Shigeo (Fujiwara Tatsuya) protects a teenage boy Tezuka Shun (Ichise Yuya) who has been forced to shoplift and encounters Shun’s elder sister Maho (Narumi Riko). The parents of Maho and Shun are on an overseas assignment and the two siblings live together. One day, Shigeo is saved by Maho just as he gets into a panic and he confides that he is in distress over the aftereffects of the bullying he suffered in junior high school 15 years ago. He has “always been in the cold sea-bed” since then. Shigeo isolates himself from society and cannot even get full-time employment. When he looks at school uniforms, he will have flashbacks of the bullying. Maho sees through Shigeo’s deep emotional scars and tries to help him. Although she is independent and hates conforming with others, she opens up to him and a relationship develops between the two of them. Shigeo shows signs of getting back on his feet again. However, Shun attempts suicide because he can no longer tolerate being bullied and this shocks Shigeo. He decides to face up to his past and meets Tachibana Ryunosuke (Oshinari Shugo), who was the leader of the bullies back in junior high school but has practically forgotten about this. Now a lawyer and the most successful of the alumni, Ryunosuke declares without remorse that “bullying will never disappear”. Shigeo gets the idea to put a drastic plan in motion even though Maho desperately tries to stop him. He attends the school reunion which Ryunosuke has planned and with his hand on the switch of a bomb, he announces to his former classmates, “Please die with me.”