Hakuouki

Tange Tenzen is made a vassal to the shogun. He is a master of the single long sword fighting style. But in order to defend the honour of his wife, Nagao Chiharu, he loses an arm, and his family is also wiped out. Tenzen then becomes a wandering samurai and is saved by Horibe Yasube, who subsequently goes on to be a vassal of the Ako domain. On the other hand, Tenzen becomes a bodyguard of Kira Kozukenosuke and ends up facing off against the Ako samurai as a one-armed swordsman.