more than the carefree life of an elementary school boy, the existence of the young shun uruma resembles a real hell. in fact, he suffers terrible mistreatment from five classmates, who consider him a guinea pig in all respects. fortunately for him, he can count on his caring younger brother and the protection of his parents. one day, however, his five tormentors also deprive him of his family. after four years, shun presents himself again before his perennial enemies.