Yukio Kyumonji (九文字 幸男 Kyūmonji Yukio) is a chauffeur of Kaede Beniya, whom he also has a crush on. He was befriended by Jiya, a Galactic Patrolman, who used him as a host to fit in on Earth. He appears in Akira Toriyama's Jiya manga, and also makes a cameo in Dragon Ball Heroes: Victory Mission.
Kyumonji and Kaede's car broke down in the mountains and Jiya appeared, saving them from bandits. Jiya had come to Earth to investigate a report from his comrade, Steth, and was with the Galactic Patrol. A vampire called Vamp was terrorizing Earth with giant flea minions. Jiya borrowed Kyumonji's body to fit in on Earth while investigating. He also experienced sexual pleasure in Kyumonji's body, having sex with a hooker whom he had saved from a thug (Kyumonji later revealed he had been a virgin until then). Jiya left Kyumonji's body and went back into his old body, while fighting Vamp's giant fleas. Vamp's giant fleas were revealed to be Mogans from the Planet Kanoi.
Jiya realized that Steth had possessed Vamp and had brought the Mogans to wreak havoc on Earth. During Jiya's final battle with Steth, Kyumonji revived Jiya's suit with Kaede's alcohol while Kaede distracted Steth. Steth left Vamp's body and tried to possess Kyumonji, but was shot and killed by Kaede.
Kyumonji and Kaede later drive away in their car, with Jiya in the back seat. Jiya tells them that Steth had come to Earth to find out if it was worth saving, as an asteroid would destroy it in one year. He says that the Galactic King will stop it now that they know it was worth saving.
Other Dragon Ball stories
Main article: Dragon Ball Heroes: Victory Mission
Kyumonji appears in the 4th chapter playing against Kaede.