In a fantastical medieval Japan inhabited by demons, spirits, and supernatural creatures, Okko is a ronin who travels the land at the head of a small group of demon hunters. At his side are Noburo, a powerful warrior hidden behind a mask, the monk Noshin, and Tikku, a young boy who becomes their companion after the disappearance of his sister. Together, they take on missions that lead them through dangerous provinces, isolated villages, rival clans, and supernatural disturbances. Along the way, the group faces both monsters and humans, while secrets from their past gradually begin to resurface.