When the daughter of a modern wealthy family crosses over as a little concubine, she will definitely shine brightly. However, she is a low-key person, and by chance, she meets a strange old woman who wants to teach her what she has learned all her life... Just learn, self-defense is important! Old man The emperor is fatuous, the feudal lords are chaotic, and the heroes are fighting for hegemony. In a bloody and chaotic world, a woman is a plaything and can be trampled on by others. How can she protect herself? A marriage decree requires her to replace the princess and kiss the prince of a certain vassal state.