Tanishi is a yakuza boss living and operating within Tokyo and the former employer of the pickpocket Myōjin Yahiko. With the poor Myōjin family owing a large amount of money to Tanishi, the gangster took their son under his wing after their death, sending him out into the city to steal and taking a percentage of the young thief's take each month, but Yahiko's pride as a shizōku would frequently get in the way of their business. Tanishi has a great deal of contempt for the fallen samurai that make up the Meiji era's rogues and considers his position as a yakuza boss preferable. However, he does appear to have respect for those samurai whose pride and skills remain strong. When Himura Kenshin enters Tanishi's lair, requesting that Yahiko be released from the yakuza boss' service, Tanishi acquiesces, realizing that the look in Kenshin's eyes is that of a true hitokiri.

He is voiced by Yoshisada Sakaguchi in the Japanese version.