Shichiroji

Kambei's "right hand man." Kambei and Shichiroji fought in the Great War side by side and thus have become the best of friends. He temporarily leaves behind his successful post-war business, and with it, his "girlfriend", to join Kambei in battle once again. Unlike the other samurai, Shichiroji uses a kamayari as opposed to a katana that the other samurai use. He has a prosthetic left hand which has a grappling hook capability. He is often nicknamed Momotaro, from the traditional Japanese tale, as he was found by his girlfriend, Yukino, badly injured after a battle floating down a river inside a capsule reminiscent of a peach. (from Wikipedia)