Moondoggie is Gekkostate's second-newest pilot after Renton joins the crew. He started out managing the LFO catapult and launch systems aboard the Gekko, but eventually stepped up as the group's head pilot when Talho had to step down—he's the only other licensed pilot they've got. His official name, visible on his pilot's license in episode 34, is James Darren Emerson, though the crew mostly calls him "Doggie" for short. Renton's taken to calling him "Doggie-niisan" (or "Brother Doggie" in the English dub), treating him like an older brother figure.
The Japanese version gives Moondoggie a thick Kumamoto accent that kicks in when he gets emotional, while the English dub has him slipping into surfer speak now and then. As the series goes on, his screen time shrinks, and he's mostly shown doing what he does best—piloting the Gekko and pulling off some wild evasive maneuvers to keep the ship in one piece during firefights.
Content compiled by AnimeList.moe from publicly available sources.