-"Tulip Prison". This is a prison where only sex offenders who are judged to be "impossible to rehabilitate" are imprisoned nationwide. The ninth correctional facility is a prison built on an isolated island in middle of an ocean, where no one can escape. Minato Shuuichirou is a boy who lives in Tokyo. He got the nickname of "naked man" from the police. He couldn't tolerate the existence of clothes and couldn't stand being clothed. He repeatedly kept exposing himself everyday on impulse, even risking his life. On one day with beautiful illuminations, he was arrested for public obscenity and obstruction of official duties. He defended himself in court pleading that his exposure was an act of art, but his claim was never accepted. He was found gulity of assault on the police and repeated obscenity. And he was sentenced to ten years' imprisonment. He was also judged to be "impossible to rehabilitate" and imprisoned in the Tulip Prison. Can an exhibitionist survive in this prison haunted by demonic prisoners? This prison of sex offenders called "HENTAI" is by no means a paradise.