On the sacred Mt. Kafuku, a spreading corruption known as defilement has overrun the mountain villages and unleashed malevolent spirits called the Seethe. Soh, a masked warrior, is charged with protecting Yoshiro, a divine maiden whose purification rites can cleanse the taint and restore peace to the land. By day, Soh clears the villages and frees their trapped inhabitants; by night, he rallies the rescued villagers to defend Yoshiro as the Seethe pour forth from torii gates. Together they press ever higher up the mountain, striving to lift the defilement and return Mt. Kafuku to serenity.