Blackstone Code - Chapter 2:

Just before being summoned to another world, the protagonist’s summoning medium was secretly swapped by someone. As a result, he was not summoned as the “Holy King” but instead as the “Sex King.”The magic he can use includes water magic in the form of lotion, fire magic as candle wax, and his summoned beasts include a wooden horse used for punishment…Branded as “vulgar,” “useless,” and “filthy,” he is rejected, has his engagement annulled, and is ultimately exiled. However, the one who picks him up is a princess from a nation where the sex industry is legal.Using his modern knowledge, the protagonist begins rebuilding the nearly bankrupt sex kingdom. He introduces new fashion trends unknown to this medieval world and uses his authority as the Sex King to subjugate the girls. He then establishes modern sex service techniques.The protagonist's method of leveling up is through intimacy with his heroines (his concubine maids). The more intimate he gets, the stronger he becomes, and the wealthier the kingdom grows.However, the surrounding great powers will not stand idly by and allow a flourishing nation full of women. Thus, the flames of war are ignited.Utilizing his creativity, adaptability, and cunning, the protagonist repurposes his sex-related magic for military applications and overwhelms his enemies.As he gradually awakens to the path of conquest, he begins walking the road of a ruthless emperor. However, by his side is always a heroine, a celestial beauty who keeps his heart from straying too far…

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

I accidentally changed the whole world, the resurrection of the dead, genetic variation, recovery of the qi, mountain and seas reborn, land and seas expanded and evil spirits have started to appear.

Ghosts are now commonplace. Some people now have three heads and six arms. Some people have obtained martial arts techniques and ordinary people are now just cannon fodder.

Fortunately, I have acquired an ability which can make various items mutate.

books into martial arts or cultivation manuals,

fruits into precious treasures of heaven and earth or poison that you can only imagine and…

weapons, that can split the earth or gain sentience!

- Description from Novelupdates

A High School Boy without friends, Odamori Tooru reincarnated into a Fantasy World after a bus accident on a School Field Trip. The job that was drawn 『Slavemancer』a Cheat occupation that dominates the minds of other.