Kujaku's power is eating him alive from the inside, and every fight is him losing ground to something he can't control. The OVA spends three episodes building toward a confrontation that stops mattering the moment he understands what he actually is. Watching a character race against his own nature, knowing the destination ruins everything he's been trained to want, that's the real horror here, not the minions.
Kujaku carries a curse in his blood. Born under circumstances shrouded in mystery, he's spent his life under the protection of priests who taught him to channel his overwhelming supernatural abilities toward righteousness. But his past refuses to stay buried, and neither does his enemy. Siegfried von Mittgard knows what Kujaku is meant to become, and he wants that power for himself. To rule as the Regent of Darkness, Siegfried needs to stop the young mystic before he fully awakens to his true nature. He sends waves of demonic servants and killers after Kujaku, each more vicious than the last. Caught between protecting himself and discovering who he really is, Kujaku finds himself racing against time. Every battle brings him closer to understanding his origins, but also closer to losing control of the dark force living inside him. The question isn't whether he can survive Siegfried's onslaught. It's whether Kujaku can master his destiny before the power consuming him from within takes over completely.