LONE: The Journey Beyond - Chapter 53: Dungeon Dive!

Yang Ge had never been the greatest in the world.But later, everyone in the realm of martial artists said he was the greatest in the world…PS1: This is a story about friendship, ideals, and reconciliation.PS2: The second place in the world is also goodPS3: People strive for fame and fortune, struggling for a lifetime, and finally realize that it's just a bubble

Suo Fei, a veteran NEET has spent three days and three nights strategizing his way through the highly explicit H danmei game masterpiece “Yalance”. Furthermore, he was able to capture all nine little shous from the nine great races. However, as the final, 10P feast was approaching, he unexpectedly transmigrated. He transmigrated into the real country of Yalance…

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

Upon meeting the girl who would become her adopted younger sister, the duke’s daughter Christina regained memories of her previous life. Through those memories, she learned that her new sister, Mishuli, was the heroine of a certain story. And though the story depicted a Christina who abused her sister, the real Christina turned into a siscon who spoiled Mishuli to no end.