Kai was living a peaceful and secluded life with his special martial arts teacher Gankutsuo, until the day he rescued a beautiful girl, Lee Shuurei, who was tumbling down a waterfall. He has no idea what she means when she asks about a "Tenraimon", but Kai is soon drawn into her problems when her pursuers arrive. Meeting her will change the course of Kai's life! (Source: MU)