A Hentai System in the World of Danmachi - Chapter 15 - 14 - The system answered me.

Jiang Yu was a small mermaid who couldn’t sing. He had always felt inferior because of this. Not until he came to shore to find the father of his baby did he discovered that his talent turned out to be acting. Since then, he had trampled on the scum man, going on the acting road all the way, and progressing triumphantly.

Qin Shen: ??? You ran away after sleeping with me, and you still call me a scum man?

The not yet met Jiang Yu: Oh, it’s a small star who wants to hug my thighs.

The after contact Jiang Yu: Really fragrant.

Qin Shen found that things around him often disappeared, at first it was handkerchiefs, then ties, and then his shirt. And every time he lost something, there will be more pearls around him. One day, he caught all the things he had lost in that room, and he saw a little thief in his pajamas.

The little thief Jiang Yu is not happy, pointing at the jar of pearls, I am not a thief, I have money for you.

- Description from Novelupdates

Zhong Yuhuan had transmigrated into a book and became the female supporting character who was destined to die an untimely and tragic death. Coincidentally, her family adopted two boys — the male lead and the villain of the book!

The male lead of the book would become a superstar in the show business and the villain a super successful and powerful businessman.

Zhong Yuhuan thus began her life of raising the male lead and the villain while faceslapping other scums. She would grow up quickly and live the life of the rich and powerful Mary Sue!

- Description from Novelupdates

Shi Jin once read a book. It was supposed to be about satisfying the desire for vengeance.

The main character, also named Shi Jin, was the sixth son of his harem-novel-protagonist-like father. All was well—while his father was alive. But after his death, Shi Jin’s five elder half-brothers tormented him, eventually leading to his death. The protagonist was reborn, determined to take revenge, and… the novel was discontinued.

That day, Shi Jin almost spat blood and dropped the book into a shredder. The next day, he died in a car accident. Somehow, when he came to, he had transmigrated into a teenager, a youth also called Shi Jin.

There was only one problem. His father had just died. His older brothers were about to torment him…

Shi Jin: Let’s eliminate my brothers’ hatred, my goal is to keep my life!

- Description from Novelupdates

Lingyun, a fierce and savage cultivation genius takes over a dead teenager’s body. Coincidentally, they are both named Lingyun. Set in a alternate version of the 21st century, teenager Lingyun has been killed by someone with a grudge.

- Description from Novelupdates