Constance is just an innocent girl. Nothing wrong with that, right? She is a bookworm, sensitive little thing, stubborn, short-tempered, sarcastic at times, curious, and harsh. What happens when a crackling noise woke her up? Is it dangerous? What is it? Nickolai is a demon boy. Nothing wrong with that except he kills and tortures people for his uncle Satan. He can hide his songs and tail when he is in public and make them appear when he wants. What happens when he sees a human girl touch his dragon egg, which is impossible because an angel or human can't touch it without being burned? Is she a demon like him or not? Is she a threat to him and his kind?