Kawaguchi (川口 Kawaguchi), Morty in the Vitello and Phuuz dubs, works at Futaba Corporation and is 24 years old. Hiroshi is his senior, or senpai, so Kawaguchi always looks up to him almost to the point of him thinking that Hiroshi can do no wrong. They often go out drinking and to lunch, together. His surname is Kawaguchi, Saitama and the first name is unknown.
He's pretty shy with girls. He fell in love with Yumi Kusaka, Hiroshi and Misae tried to make them both go on a date, but it didn't work.
Japanese: Daiki Nakamura