In a world where magic has seeped into everyday life, humanity battles hordes of monstrous Fiends that pour through mysterious Hollows. Riku Mori, an F-rank Hunter struggling to survive, stumbles upon a powerful artifact - the Gaio Driver. This transformation device grants him the power to become the armored hero, Gaio. Thrust into a dangerous new role, Riku must confront his own fears and insecurities as he learns to wield his newfound abilities. When the ruthless Crimson Fang crime syndicate threatens his home and loved ones, Riku partners with a determined detective to take them down. As Gaio, Riku faces an impossible choice - embrace the monster within or become the beacon of hope his city needs. In this thrilling superhero saga, the fate of the city hangs in the balance as Riku fights to protect the innocent, uncover dark conspiracies, and ultimately find the strength to become the hero he was always meant to be.