Yuu Kamishiro is a tormented soul with no place in society. His peers constantly abuse him at school, and he finds that he does not fit anywhere. Out of desperation, Yuu stops attending school and ventures into the night in search of a safe haven where he will be accepted. As Yuu roams the streets, he begins to believe he has found his place in society and a way to gain acceptance: in a world of violence and lenient law. Yuu takes up his fists to gain the strength to protect himself, training and refining a single boxing punch. After honing his fists, Yuu wanders the streets once again, defending himself from street thugs. Building a reputation as the "Thug Hunter," Yuu finds that his name has been attracting all sorts of people seeking him out for a brawl. Fight after fight, Yuu exchanges blows to find his place in the twisted and dark society of the streets, all while battling the darkness welling up within him. The stronger he becomes, the closer he is to reaching his "holyland."