Yuu Kamishiro

Yuu is shy, anxious and socially awkward. Years of bullying leave him with little confidence in ordinary social situations, and he initially struggles even to understand why other people might want to befriend him.

Fighting produces a striking contrast. Once his body begins responding to danger through trained movement, Yuu can display persistence and aggression that seem incompatible with his everyday demeanor. He is frightened by violence but also drawn to the clarity it gives him.

His greatest strength is persistence. The same obsessive repetition that builds his one-two becomes a broader willingness to practice movements until his body can perform them under pressure.

Yuu begins with boxing learned almost entirely through repetition. His jab-cross combination has been practiced so many times that he can deliver it quickly and naturally even without conventional gym training.

Experience gradually expands his arsenal. Masaki Izawa helps him understand distance, timing and the differences between sporting martial arts and street fighting, while Shougo Midorikawa exposes him to kicking mechanics and body rotation.

Yuu also possesses exceptional adaptability. He learns directly from fights, studies what defeats or injures him and incorporates practical solutions into his developing style. His conditioning, footwork and ability to remain dangerous while frightened all improve substantially.

Yuu begins the story isolated from school and society. After discovering a boxing manual, he spends enormous amounts of time practicing punches alone, initially using repetitive training as an escape from his own thoughts.

When delinquents attack him on the street, his trained one-two proves unexpectedly effective. Rumors of a mysterious fighter hunting delinquents spread, even though Yuu is not deliberately seeking them out.

The reputation brings increasingly dangerous opponents and friendships with people such as Shinichi Kaneda, Masaki and Shougo. As Yuu becomes stronger, his struggle changes from merely surviving fights to deciding whether the street and violence have become his identity. By the end of the story, he remains connected to the streets even as several older fighters move on from them.

Masaki Izawa becomes Yuu's most important fighting mentor. Masaki Izawa recognizes both his talent and the psychological danger behind his growing attachment to street fighting.

Shinichi Kaneda is Yuu's first close friend and one of his strongest links to an ordinary social life.

Shougo Midorikawa begins as an opponent before becoming Yuu's friend and training partner. Shougo Midorikawa teaches him important principles behind kicking and body rotation.

Mai Izawa is Yuu's classmate and Masaki's younger sister. The two gradually become emotionally close. Their mutual attraction eventually becomes explicit, although Yuu's attachment to the streets complicates the possibility of an ordinary relationship.

Iwado is one of Yuu's first experienced martial-artist opponents and later gives him advice.

Taka becomes one of Yuu's dangerous weapon-using opponents.

Tsuchiya initially fights Yuu but later becomes part of the broader group around him.