Elias Arthur Zebulon, a powerful demon, gets caught in a dimensional rift and later finds himself on Earth. In the midst of his distress, Arthur transforms into a cat just before he loses consciousness, in order to avoid being conspicuous. Cerise Riven is a twenty-four year old woman who lived alone. Aside from reading novels, she never really had an interest in anything. One day, lured by a cry she heard, Cerise picks up an injured black cat in a dark alley and brings it back to her home. In a world where almost every being longs for freedom, Cerise questions its authenticity and is determined to find what it means to be truly free—even if that means she has to take the hand of a demon and live in his cage.