Sakyounosuke Kanna

Born in London to a British royal navy vice admiral father and a Japanese mother, formerly a tayū in Yoshiwara, Kanna Sakyounosuke is tasked with being the bodyguard of Katsu Kaishu, as part of a request from H.S. Parkes, the head of British mission in Yokohama, and is an extremely talented fighter, armed with two guns, each of the Remington New Model Army Conversion type.

(Source: Wikipedia)