Kenji Yamabuki is a childhood friend and former classmate of Yumi Sakurakouji and of Akira Kazami and now friend to Rex Salazar and Ren Johnson. He was originally a world traveler. However, after fighting Zag-RS alongside Rex and Yumi, he was invited to join Providence. He is generally friendly only towards his friends.
When Kenji and the other Generator Rex characters were added to the game, his model had his shoulder-length hairstyle. However, Kenji has now his hair in a short, messy cut, but his model has yet to update with his short-haired appearance.