On the night of a full moon, Didi makes love for the first time with her boyfriend Johannes, who then dies in her arms. The next day, Didi meets two women, Kati and Nadia. They reveal that she is a nymph, and warn her that she must quickly learn new rules and beware of Satyrs who have chased their kind since the dawn of time.

Where does Didi come from, who are her real parents, and why does she have a tattoo of a knot?