Sean Firestone (Shane Firestein in the original Japanese dub) is a Gear Master that Kouya met in San Francisco. He is the creator of Ark Cavalier and Vort Grenade. Unknown to the majority of the Crush Gear world, he is actually the legendary Gear God and the older brother of Gina Firestone.
Sean is seen to have turquoise eyes and greenish brown hair. His usual outfit consists of a light purple jacket with a white shirt underneath, and they are worn with the sleeves being rolled up. He also has suspenders, a pair of dark gray pants and brown shoes.