Nanako Tsukishima is a determined fighter who dedicates herself to intense daily training in order to achieve the world championship title her brother could not win. One day, she is suddenly kidnapped and imprisoned in a basement. There, she encounters Yuki Sakurai, the warden of a deathmatch tournament arena. Terrified by his presence, she soon realizes his intentions go beyond mere confinement—he has a far more sinister plan in motion.