MTL - Rebirth of the Supreme Celestial Being - Chapter 148 Baihe Xianqi

Su Ran, a music prodigy, woke up transmigrated into a book.

At that point in time, the main story arc in the book had already been completed. As a villainess female supporting character, not only did she need to take over the original owner’s pitiful life in poverty, she also gained an instant son right at his rebellious period.

Ten or so more years from then, the son would turn into a twisted, evil villain. He would appear in one of the extra chapters to pick on the male and female lead’s children.

***

Su Ran: Son, you shouldn’t be too outstanding.
Su Han: Why not?
Su Ran: ’cause you will be killed.

Su Ran: Son, would you like to learn music from me and become a zen, little fairy boy who only needs to drink dew.
Su Han: No, I want to go into business so I can support you.

- 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

Upon awakening, the apocalypse's metaphysics master, Nan Li, found herself as the lost Sixth Miss of the Anyang Marquis ManorThinking it would be a story of abuse, she never expected all five of her brothers to dote on her one after another!Nan Li shouted, “Stop pampering me! In fact, I can do everything, from capturing ghosts, exterminating demons, divination, physiognomy, to healing and saving people. I'll lead the family to rise in power and wealth!”Accidentally saving the Ninth Prince, who held great power in the court, Nan Li found him renowned for his cold and unfeeling demeanor. However, he became utterly addicted to pampering her and refused to take other concubines.The scheming and malicious women were angry, shouting, “The prince lacks heirs, how can this be allowed?!”Nan Li pointed at the line of little ghost-catching disciples and said, “I'll cure your poor eyesight!”The Ninth Prince lifted her in his arms and said, “We have a bit of thin property that needs to be inherited, so we'll have a few more children.”Later on—Nan Li looked at the continuous immortal mountains and the room full of treasures, her mouth twitching, “I thought you had a throne to inherit, what's going on now?!”