The anime adaptation of "Lilitales", a doujin game by tunnel No,73 which has gained huge popularity!

A knightess Luna goes out to rescue the Princess Jill who has been abducted. While gathering information, she sells herself to a slave trader Batil.

On the other hand, Jill is restrained at an underground slave auction. There she is exhibited as an object to be sold and eventually loses her virginity. Despite Luna's effort to save her, Luna also falls into the hands of the villain. Cless comes to rescue them, but...