Matsumoto, Kouji

A veteran male Gunpla Builder who challenges Haru to his first duel, with Haru's Beginning Gundam at stake. He's a member of the SGOK idols group. He is a carefree young man, who has two young females that seem to follow him, while getting his butler to make and customize his gunpla. It appears that he cracks very easily under pressure.

He later reappears in the final match in his mech that he personally built this time, but was defeated incidentally by Haru during his battle with Boris.