The story begins in 1629 Shizuoka during Tokugawa Tadanaga's rule. The daimyo staged a tournament where the participants fought with real steel Japanese swords rather than bokken, against his vassals' strong objection. The story revolves around the first match between the one-armed swordsman Fujiki Gennosuke and the blind samurai Irako Seigen and deals with the circumstances that led the two to participate in Tokugawa's tournament.
Komori Yui lives her life together with six brothers (by father's side). However, it is not the common daily life! In fact is quite a radical life, she is oppressed by them, and blood is demanded, as they are all vampires!