Although the era of the samurai is long gone, Takeshi Chimatsuri strives to preserve the spirit of duty by wearing traditional attire and carrying a sword daily. However, when Kageri and Akari Toki, daughters of a ninja family, transfer to Chimatsuri's high school, their abrupt encounter may well bring the entire institution to its knees. The Toki sisters have vowed to reclaim an heirloom sword that Chimatsu's father won in a duel years ago—and are more than ready to employ underhanded tactics to achieve their aim.