Yūta Tomonaga is one of the protagonists of the Brave Police J-Decker television series.


Yūta stumbled across Deckerd in the abandoned warehouse where he was being constructed by accident, and began to visit the robot regularly. Because of this interaction, Deckerd developed a "heart," which would later show up in all subsequent Super-AI units constructed. Memories of Yūta were also present in all of these subsequent units.

Commissioner Seijima later made Yūta the head of the new Brave Police unit. He dispatched the team on missions and often joined them. He also possessed a badge that allowed him to issue the unification commands needed to form J-Decker, Build Tiger, Super Build Tiger, Duke Fire, and Fire J-Decker.