Abused in the back palace, Lusienne remembers her previous life with the shock of a blow to the head.

…You're lying, right? Lusienne la Verrier is the name of the villainous princess in that otome game I liked. But wait, how old am I now? Isn't Lusienne's life too hard from the very beginning?

This is a story about a young princess (who surprisingly doesn't care) who has been oppressed despite being royalty, and a (yandere) assassin who gradually begins to think that such a pitiful princess is cute, and they become friends ten years before the original story.