Though the time of the samurai has long since passed, Takeshi Chimatsuri does his best to keep the spirit of duty alive by wearing traditional clothing and carrying a sword with him every day. However, when Kageri and Akari Toki, who hail from a family of ninjas, transfer to Chimatsuri's high school, their sudden meeting may just bring the entire place to its knees. The Toki sisters have sworn to take back an heirloom sword that Chimatsu's father had won in a duel years before—and are more than willing to use underhanded tactics to accomplish their goal.