Mia, a corporate drone, is transported to an upside-down world ruled by giant beasts where humans are kept as pets after working overtime. She is bought at a high price by Nina, a giant ragdoll cat. She meets other companions who also retain their human memories, and discovers that Nina is actually the orange cat she rescued in her childhood. The group fights against the conspiracy of unscrupulous merchants, goes through dangerous situations, and dismantles the evil deeds of the black market. Mia refuses to return to her original world, and forms a warm cross-species big family with her lover, companions, and Nina.
