MTL - Evil Wang Pampers His Ghost Doctor Fei - Chapter 4486 vent your anger

Twenty years ago, she was taken in as the Lin family’s young heiress through a twist of fate. But mistakes would eventually be corrected one day. When the real daughter of the family returned and her foster parents begged her to stay, she obliged. Unbeknownst to her, this was actually a scheme disguised as familial affection. They only kept her around to squeeze her dry of all her value!

Another entry in what you can call the Proto Harem Series: the books written before the Harem Series that take place in the same world.

It’s about a swordswoman whose student is captured, so she goes to rescue her.

After choking to death on a watermelon, Rong Jiahui thought that she would enter the netherworld and be reincarnated.

But when she opened her eyes, she discovered, to her very horror, that she had returned twelve years into the past…

Looking at the beautiful and awkward “little brother” that would be conferred the title of Marshal in the future for outstanding military service, she almost let out a snort of laughter.

She firmly decided to hug the thigh of this little brother, and climb to the top of her life!

The plan was beautiful, but it had just one problem.

Why had this little brother… suddenly turned into…

A little sister…

- Description from Novelupdates

Mo Yan was an illegitimate child of a rich family and was arranged by her mother to take the place of her sister in marriage to a poor man in order to fulfill the marriage contract set by the previous generation, allowing the Mo family to get their hands on that substantial dowry.