Years after the Bakumatsu, a bloody revolution in Japan, a red haired girl named Akasuki saves Kaoru Kamiya from being killed by a guy claiming to be the legendary Hitokiri Battosai. After, she helps Kaoru save her dojo and ends up staying with her. The two quickly become best friends and soon add a new student of the Kamiya Kasshin style: Yahiko Myojin. Then one day, she encounters someone who she'd been looking for ever since the Bakumatsu ended.