Matsukiyo
Matsukiyo (Matsukiyo; Bootleg: Sungki) is a friend of Shigeki who appears in both Keitai Denjuu Telefang: Speed and Keitai Denjuu Telefang: Power.
He is something of a child genius, and deeply interested in the Denjuu world, which he had never visited before. After he and Shigeki accidentally arrive there via the D-Shot that Shigeki picked up, Matsukiyo stays with Musa in Toronko Village and gives Shigeki advice during the course of the story.
In Telefang 2, Matsukiyo appears as a professor living in the human world. He offers rewards through the D-Shot's Wanted application, in exchange for information on specific Denjuu.
In the manga
In the Telefang 1 manga, Matsukiyo takes a much more active role than in the games, exploring the Denjuu world with Shigeki. He befriends a Waratah in Toronko Village, which becomes his partner Denjuu.