Hanagaki Takemichi lives an unsatisfying life right up until his death. Waking up 12 years in the past, he reckons with the eventual fate of his friends and tries to prevent an unfortunate future.
An unemployed man learns that his ex-girlfriend was murdered. He suddenly finds himself travelling through time to his middle school years and has chance to change the future and save the girl. He aims to rise to the top of the most brutal delinquent gang.
Hinata is murdered again by the Tokyo Manjikai Gang in front of Takemichi. In order to save Hinata, Takemichi travels 10 years back in time again. Takemichi has to change a key case that can save Hinata. The key case involves a sad incident that occurred to 6 men, who later formed the Tokyo Manjikai Gang.
Driven by a single-minded determination to protect his friends and save Hinata, Takemichi Hanagaki enters a gang war with the hope of altering the course of fate and creating a better future for everyone.