OVA
Description
Koichi begins as an ordinary young man, chosen by converging ancient supernatural forces. Dormant within him lies the power of Takegami, the warrior-god Susanoo, destined to fight resurgent evil. This connection flows from ancestral ties; Koichi shares heritage with Susanoo's original mortal host.

He fiercely resists this destiny, displaying profound reluctance towards violence despite the awakening threat. The return of three ancient dragons, bent on devouring human souls and destroying the world, marks him as the prophesied figure to stop them. His refusal stems from personal aversion to conflict and horror at the bloody consequences of wielding Takegami's power.

Susanoo exists as a distinct consciousness inside Koichi, asserting control during confrontations. The deity demands Koichi "succumb to my will" to access battle power, creating persistent internal conflict. Susanoo embodies an assertive, battle-ready persona starkly contrasting Koichi's hesitant nature.

Koichi's childhood friend, Terumi, deeply influences his actions. Her transformation into a dragon host, driven by her own wishes, intensifies his personal stake. Protecting her becomes a key motivation, gradually compelling him towards accepting his responsibilities despite misgivings.

When fully possessed by Susanoo, Koichi physically transforms. He manifests two distinct battle forms: a beast-like armored state resembling a "mecha dragon" and a giant samurai warrior incarnation.

His development progresses across three pivotal conflicts. He confronts the first dragon while still resisting his role. Preparation for battling the second, the Dragon of the Heaven, marks a shift towards cautious acceptance guided by the priestess Sayoko. The final battle against Hiruko, an ancient evil and Susanoo's sibling deity, forces full engagement. Learning of Susanoo's historical defeat by Hiruko and the death of the previous host reveals Koichi's own mortal vulnerability.

Facing Hiruko involves reliving ancestral memories of the ancient battle, forcing Koichi to reconcile with this inherited legacy. Protecting Terumi from Hiruko becomes the immediate catalyst for summoning his remaining strength, prioritizing her safety over his fears. The outcome ties to his ancestor's fate, presenting the possibility of sharing the same lethal consequence.