Martial King's Retired Life - Chapter 43Book 14:

Su Yu, who was attempting to create a second account in the VR trading card game “Yu-Gi-Oh! World Link Online”, inexplicably traveled to the game world, and even had his own NPC identity.Time went back to one month before the game was launched, the nameless Pharaoh was still sleeping in the body of the high school student Yugi Muto, and the Duel City with cross-generational significance had not yet started.When the game was officially launched, players logged in and found that there was a new NPC in the game that was not in the original game.Yuei Vu: Do the players over there want to buy a booster box? Fifty-one packs, five hundred and ten cards, fair price, no cashback!The players stared directly at the Pot of Greed marked as UR in the product list, their eyes were burning, and the same thoughts came into their minds…

Every novel has a low IQ supporting female that serves as a foil to the female lead’s good and beautiful sides. She’s the stepping stone on the path of love between the male and female leads, destined to live her life doing stupid things until her tragic end.

One day, all of the villainous supporting females came to their senses. They began to rebel! And quit! For the sake of world order, the System found a human to take their place.

World 1: The female lead risks her life to shield the male lead while the supporting female quakes in a corner (and watches the show)

Male Lead: ?? So you never loved me.

Supporting Female: He finally found out, looks like my job was a success. The end of the year bonus is mine!

Male Lead: ?!

A fun and breezy quick-transmigration story~

- Description from Novelupdates

Everyone wants superpowers, including Alden Thorn.But even if he's lucky enough to be one of the few humans granted magical abilities by the extraterrestrial System that's been running things on Earth for decades, his goal of being a battlefield support hero is still a long way off.He's got determination on his side and maybe a murderous alien desk clerk, too.The universe is a complicated place. Alden's about to meet it.

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