Makai Law decrees that any human stained by the blood of a Horror should be killed, or else they will die painfully in 100 days. This is the fate that has befallen Kaoru, a young girl caught in the middle of a fight between a Horror and a Makai Knight.

Kouga Saejima—the Golden Knight Garo—defies this rule, and vows to find a way to purify Kaoru before her time is up.