Susumu Kirakuni, a 26-year-old GEAR staff member, was initially considered as a potential pilot for the giant robot Dendoh. When Dendoh instead selected fifth-grade students Ginga Izumo and Hokuto Kusanagi as its operators, Kirakuni shifted to a support position within GEAR. He adopts a big brother-like relationship with Ginga and Hokuto, dedicated to supporting them as Dendoh's pilots. To contribute directly to their mission, Kirakuni pilots the "Cellfighter" support jet, providing combat assistance and reinforcement against threats to Earth.