Hyoi and Rui, two inhuman brothers with the powers of the Dark Cat, a spiritual martial art that allows them to sense supernatural beings and turn into cats, are caught up in a dilemma involving their Dark Cat master, Jakokubo, who plans to summon the evil in humans as a tremendous feast for himself and his power. What do a group of local high schoolers have to do with his nefarious plans, and will the Dark Cat brothers be able to save their newfound friends from certain danger?