Ken was a short thin boy, he had black hair and long thin eyebrows. Unlike his two friends he was the only one to take proper care of his school uniform.
Ken was rude and spiteful, happy to make a problem of himself.
Ken was a member of a gang of young delinquents, at one point he, Go and Dosu-Roku follow the girl Miki Makimura and her freind Akira Fudo home, taunting them. Miki retaliates and insults them before slapping Ken and Go in the face. Dosu-Roku grabs her arm furious at the abuse hurled at them and he tells Go and Ken to block the path for Akira, however she is saved by the sudden arrival of Ryo Asuka who chases the gang away with a gun.
Later after Akira had become the eponymous Devilman, Ken, Go and Dosu-Roku again attack Miki and Akira armed with dosu blades, however this time Akira steps in and beats with ease thanks to his new powers.
- In the Birth OVA, Ken and Go's roles are replaced by Dosu-Roku and Manjiro , with Masa taking charge.