Nina's big sister has been taken by the demon lords who rule the land. Everyone around Nina has accepted this — the mistreatment, the fear, the condition of living under something more powerful. Nina has not. With her friend Ignis, she attempts to infiltrate the demonic manor, and the two of them immediately find themselves trapped somewhere far worse than they anticipated. As they uncover what the lords have been concealing, Nina begins to encounter questions about her own nature that she does not know how to answer. Whether they survive the night — and what Nina discovers about herself along the way — is what the story is made of.