Hikari's father is a carpenter and lives in the old shopping district of Tokyo. As a fan of pro-wrestling, he taught Hikari how to fight when she was a child. Through his interest in pro-wrestling, Jiro met Kei's father and they introduced their children to one another when Hikari and Kei were six years old. After Hikari was defeated by Kei, she begged her father to allow her to enroll in the same schools as Kei in order to obtain the opportunity to defeat him. Headstrong and hot-headed like his daughter, Jiro agreed and has since supported her endeavours to defeat her rival. He and Kei's father are friends.