Unken is a martial arts master and the father of Kōshi. He wants his son to follow in his footsteps, but is unable to persuade him to train in the martial arts. He heads the dog family of the Zodiac Masters of Japan. He and Sendayū are both friends and rivals. An old school photo shows that, although he now has a rather odd face, he was once the spitting image of his son. This has caused Kōshi some concern for the future.
