Gasuke is one of the head officers in Tanishi's yakuza and often the man who had to deal with Myōjin Yahiko before the latter refused to be Tanishi's puppet.


Fed up with the boy's stubbornness and pride, Gasuke frequently resorted to violence in order to force Yahiko to comply with his wishes, dealing out vicious beatings in his boss' stead. After Yahiko bites him in the groin to repay an insult to his parents' name, Gasuke draws his sword in vengeance, but is interrupted and swiftly defeated by Himura Kenshin, who convinces Tanishi to let Yahiko go free.


Gasuke is quite skilled at Kenjutsu as he easily defeats Kamiya Kaoru, who is the assistant instructor of the Kamiya dojo. However, he is absolutely no match for Kenshin, who literally sends him through the roof.