Possessed and Made a Concubine: I Snatch the System and Rise

Daughter of a general's household, Lin Ruochu is possessed by another soul on the day of her fifteenth birthday ceremony. The transmigrated woman, who was abducted by a system, used every possible method to clear the route with the Marquis household's eldest son, ruining Lin Ruochu's reputation and alienating everyone around her. In the end, Lin Ruochu was kept in the marquis household as a concubine, like an outer room woman.

After taking her body back, Lin Ruochu swears to set her ruined life back on track. Unexpectedly, while fighting against possession and the system, she gradually comes to understand the truth of this world.

An unconventional household struggle, with a worldbuilding mystery; all of the loose ends will be tied up later.

The female lead mainly relies on her brain, and the system cheat ability is not very strong.

There is a couple, 1v1, male lead is chaste, female lead is remarried.