Kengo is both the owner and the chief gunner of the Gekko and is one of the founding members of the Gekkostate. It is speculated that he served in the military with Holland, but he is known to be the owner of the Gekko. He once stated that "[he] would not have let [Holland] have the Gekko if [he was]...", cutting off his statement before actually revealing the reason. His marksmanship skills are exceptional and his aim is legendary among the other crew members. Holland refers to him as "Maestro" from time to time. He also enjoys painting and his works are often seen in ray=out.
- In Eureka Seven: The Day After, he resigned from the Gekkostate on April 27, 12006, and used the Gekko as a shipping business with Woz, Jobs, Moondoggie, and Gidget.
- In the final chapter of the manga, he is last seen working in loading ship cargo.