MTL - Raising Evil Spirits - Chapter 8118 : Chamber

Lee Jin Woo once lived a dismal life.
He lived pitifully on a day to day basis in his five-pyeon studio filled with mold.

Then, one day, he died in a sudden fire.

When he wakes up, he finds himself inside a novel.
But there’s just one issue…
He had become the novel’s villain!

Leiyin accidentally crossed into the One Piece World, and accidentally obtained the Naruto System.

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 had been abroad to do medical volunteer work, when I was swept up in a civil war. I was killed by a rebel soldier, while taking a bullet for a patient. But when I finally woke up, I had become a child?!?And in front of me stood a destroyed carriage and a group of oddly dressed people, who were unconscious!“It’s just like a Murim world.”As I hurry to perform first aid in an attempt to save even one person, I realize that this world is that of [The Supreme Demon King], a Wuxia novel I’ve enjoyed reading.After meeting the rescue team of the ‘Three Great Doctors’, I found out that one of the person I saved was the protagonist of this novel, the future Demon King ‘Yeo Haryun’!“Hey, since I’m indebted to you for saving me, call me ‘hyung’.”For saving his life, I become sworn brothers with the future Demon King, and the White Dragon Godly Doctor, one of the most knowledgeable people around, recognized my potential and took me in as his disciple. This is the story of how I became the greatest physician in Gangho!