Series by 和久井健

Hanagaki Takemichi, a 26-year-old down-on-his-luck freeter, learns that his middle school ex-girlfriend Hinata and her brother Naoto were killed by the Tokyo Manji Gang. After a near-death experience, he inexplicably time-leaps back 12 years to his teenage days, meeting Naoto and vowing to save Hinata. As Takemichi infiltrates the gang and befriends its leader Mikey and vice-leader Draken, this gripping tale blends action, loyalty, and the desperate fight to change a tragic future through courage and unbreakable bonds.