The stepfather of a noble family

Introduction:

Gu Siwan traveled back to ancient times and became an unpopular concubine of the Prime Minister's Office. She has tried her best to be low-key, keeping a low profile, and keeping her tail between her legs as a person. However, the eldest sister still bullies her, and the aunt still dislikes her and wants to marry her to the Crown Prince of the Marquis as a sequel. Could it be that this prince has some hidden illness? You must figure it out, otherwise, if you marry recklessly, the bitter days will still be ahead