The Insider System - Chapter 16: Open Ended Plan

(Non-system, multiple female MCs, both good and evil)Fang Ling, who possesses the Chaos Sacred Body, was fiercely fought over by various forces since his birth. His heart, right eye, and treasured bone were successively taken away...After many twists and turns, the critically ill Fang Ling was placed in front of an ancient temple by a kind-hearted person. No one knew that within this ancient temple, five unparalleled masters were in seclusion. They had been hiding there for tens of thousands of years, suppressing the Immortal Heart of the Demon Ancestor.When the Immortal Heart erupted, the five masters were unable to contain it and took a desperate risk by implanting it into the infant's body. The fusion of the incomplete Sacred Body and the Immortal Heart led to the birth of a peerless monster...

As Shin Youngwoo has had an unfortunate life and is now stuck carrying bricks on construction sites. He even had to do labor in the VR game, Satisfy!

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

Martial Soul, the essence of innate talent, encompasses the grade of countless stars, with one to three stars being Low Level, seven to Nine-star being Advanced, and a Ten-star Martial Soul as a Heavenly Gifted Spirit, known as Spirit Martial Soul, one in ten thousand!The world asks Luo Cheng: “How many stars is your Martial Soul? What grade?”Luo Cheng stares at the endless galaxy within his Martial Soul and mutters:“That's a lot of billions, it's hard to count!”