Seiji Ino is a Yakuza (more specifically: Designated Crime Syndicate - Koi Group Underground) who has an obsessive compulsive fear of edges (belonephobia), which includes knives, forks, needles, some fish, and even table edges. Seiji is known in the criminal world as "the wise seiji"; he shows this by saving a fellow member (his brother) from a rival group through challenging Yoshiyasu's (rival group leader) to Russian Roulette. He almost loses his mind when Irabu gets Mayumi to give him a vitamin shot. His Wife who runs a bar with Seiji puts a deposit on another bar that's owned by Yoshiyasu's syndicate, this causes more friction between the two factions...