Gaoh rules the formidable Black Steel Castle, serving as a minor antagonist. His forces repel repeated assaults commanded by Reina, an officer under Raoh. Confident in his stronghold's defenses and ample food reserves sustaining it for months, Gaoh anticipates betrayal within Raoh's conquered territories should his campaigns weaken. Learning Reina leads the attackers from his bodyguard Habaki, Gaoh orders her capture.

Spotting Sakuya, Raoh's strategist, approaching, Gaoh permits her entry. Sakuya disrobes completely before him to prove she carries no weapons, an act that captures Gaoh's attention. Later, Sakuya fabricates a tale: Ken-Oh murdered her parents, captured her, molested her, and she escaped. Believing her story, Gaoh vows vengeance and moves closer. When Sakuya retreats, he claims his intentions extend beyond mere pleasure.

Sakuya challenges Gaoh to pursue her in darkness, proposing intimacy if he catches her. After he captures her in a hallway, she suggests he bring light to see her naked form. When light arrives, Reina shoots Gaoh in the head with an arrow from a distance, killing him.