One Piece: Unreal Adventure - Chapter 60: The Power of a King

A world where one’s life was decided by one’s talent called Gift.
The main character Erio Scarlet who was born in the house of influential noble family that had produced a lot of Holy Knights manifested a suspicious gift Incubus in the conferment ceremony. Furthermore the skill attached to that Gift was only one embarrassing skill called Peerless.

Erio was banished from the city because there was no way his indecent existence could be permitted in a family of Holy Knights but……somehow he went through an amazing growth when he dealt with his horniness though!?

In addition when his childhood friend who was bestowed with the Gift Sacred Knight chased after the main character because of her love for him reverse ra-……did it with him, a lot of powerful indecent skills showed up and on top of that they even got bound by Master-Servant contract……!?

This was the indecent heroic tale of the boy who was gifted with indecent Gift rising in the world while [getting along] with a lot of girls.

Dreaming back to the Tang Dynasty, being an ordinary person, greedy for money, lustful, debauched and free.

- Description from novelbuddy

In his last life, he was a superstar that dominated the entertainment circle. In this life, he is a rebellious second generation wastrel.

Confronting the aunt and uncle who wants to seize the family property and getting rid of those slag friends who only know how to eat and drink…

Rong Xu: To not speak out means to perish in the silence!

From starting out as a third-rate celebrity, he had to rely on his own efforts to rise to the top of the entertainment circle, aspiring to once again sit on the throne!

Their first meeting —

Rong Xu: Hello, I’m Rong Xu. This would be our first time meeting, I would appreciate your guidance.

Qin Cheng: !!! (…Aahhh, He’s so cute! I really want to sleep with him!)

- Description from Novelupdates

In novels with a stud there is always a Senior Martial Brother like this:

In the early stages of the novel, his innate talent is high, his cultivation is good, his appearance is handsome, and he has an intelligent, cute younger Martial Sister as a fiancée.

In the middle stages of the novel, he is caught unprepared and defeated by a young disciple (the protagonist) in the sect who’s hardly remarkable at all. From then on, he falls from his godly altar and loses his brilliance. Even his young Martial Sister leaves him for someone else.

In the late stages of the novel, he continues to turn dark, going down the Demonic Path and becoming the major villainous boss. However, the protagonist still ruthlessly defeats him and his soul is eternally sealed.

Once Qin Mo opened his eyes, he discovered that he had become this Senior Martial Brother.

- Description from Novelupdates