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From ANIDB: This series details the adventures of a wandering female samurai and a Chinese martial arts "expert" who playfully refers to herself as Myao-oneesan. Tsukikage Ran, the main character, is a female ronin whose swordsmanship is second to none, while Myao's commands the often amusing but deadly display of NekoTekken (Cat Iron Fist).

On his first day at his new school, twelve-year-old Ritsuka Aoyagi meets a mysterious twenty-year-old male named Soubi Agatsuma. Soubi claims to be a good friend of Ritsuka's brother, Seimei, who was murdered when Ritsuka was ten years old.