MTL - Fishing the Myriad Heavens - Chapter 67 19

The light is here because the darkness exists. Just like that, the human realm exists because the demon realm is here. And in the great palace of the Blade Empire, a crown touches the peak of its glory before it falls from its grace. Lush Von Blade was the royal crown prince of one of the greatest empires on the southern continent. He is loyal but betrayed.On the other hand, where even the Gods fear to set a foot on, a demon lord abides. His grace and cruelty have been unseen for centuries. He is the supremacy in the three realms. While Lush is the light, he is the darkness. Each exists because the other is here.

Otaku Lin Fei crossed over to a new world…

Rare and exotic medicinal pellets? I eat them like snacks…

Powerful martial art secret instruction manuals? I can sell them like newspaper bundles…

What..You’re an absolute genius? I wreck geniuses like you for a living…

Why am I so powerful?

It’s because I have leveling system version 1.0!

- Description from Novelupdates

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

The formless ancient world was infested with despicable demons. They hunted and feasted on mankind, keeping the human civilization constantly in a weak and suppressed state.