Japan, 1955: Mario Minakami has just arrived at Shounan Special Reform School along with five other teenagers who have been arrested on serious criminal charges. All assigned to the same cell, they meet older inmate Rokurouta Sakuragi—a former boxer—with whom they establish a close bond. Under his guidance, and with the promise that they will meet again on the outside after serving their sentences, the delinquents begin to view their hopeless situation in a better light. The seven cellmates struggle together against the brutal suffering and humiliation inflicted upon them by Ishihara, a sadistic guard with a grudge on Rokurouta, and Gisuke Sasaki, a doctor who takes pleasure in violating boys. Facing such hellish conditions, the seven inmates must scrape together all the strength they have to survive until their sentences are up; but even if they do, just what kind of lives are waiting for them on the other side?

Tousuke Rokudou is a first-year attending Aomori High, a school full of delinquents. He is often bullied by his classmates due to his incompatibility with their behavior, the only exceptions being his two good friends who are also social outcasts. Frustrated at the way they are treated, the three wish they could stand up and claim the fun, peaceful school life of their dreams. However, Tousuke's life takes a drastic turn when he receives a package from his late grandfather containing their family heirloom, a scroll said to possess the power to save him from impending danger. Upon holding the scroll, a sudden glow emanates, leaving a strange mark on Tousuke's forehead. Thinking that he's received the means to free himself and his friends from their daily treatment, Tousuke is shocked to find out that its effects are far different than what he had imagined. Although his bullying continues, he realizes that the mark from the scroll acts as a charm, capturing the hearts of delinquent girls—in particular, Ranna Himawari, the strongest of them all.

Maeda is a new student in the Teiken High School. He stutters when he's nervous and he's rather clumsy. He gets noted immediately because he hits a teacher during the entrance ceremony. Some clubs search to enlist him as they see in him a force they can use to get even with other clubs. But Maeda is a loner and has only one dream: becoming a boxing champion. (Source: MU)

Otokojuku: a private school for juvenile delinquents that were previously expelled from normal schools. At this school, Japanese chivalry is taught through feudal and military fundamentals. Similar to an action film, the classes are overwhelmed by violence. Only those who survive it become true men. (Source: ANN)