Gō Mifune serves as the sheriff of Three Hawks town. He harbors an unfulfilled aspiration to become a professional racer, a dream stifled by his own lack of confidence. This creates a personal conflict with his law enforcement duties. He owns the Mach 5 vehicle, expressing emotional attachment to it and apologizing for not using its full potential while choosing to remain sheriff. When Pandora and Akubi request his help locating the destructive Shards of Calamity, he dismisses their claims and refuses. After the outlaw group Andro Band, led by Braiking Boss, takes Akubi hostage, Pandora approaches Gō Mifune again. Witnessing Pandora's resolve to rescue Akubi, he decides to intervene. Using the Mach 5, he transports Pandora to the outlaws' location. During the confrontation with the Andro Band, he participates in combat alongside Louise, employing his vehicle to create a smokescreen. This aids Pandora in rescuing Akubi and battling the outlaws. When Braiking Boss transforms into a giant monster using a Shard, Gō Mifune demands his surrender. Following Braiking Boss's defeat and the outlaws' apprehension, he resolves to leave his position as sheriff to pursue his dream of becoming a racer.