Not (Just) A Mage Lord Isekai - Chapter 61 - Wanna Trade?

Corporate slave Alexander dies with only one regret—not finishing the fantasy novel in his hands. Fate has a twisted sense of humor when he awakens as Alexander Flamingo, the perverted villain destined to be expelled and killed in that very story!Armed with complete knowledge of the original plot and a mischievous “Harem King System,” Alexander plans to rewrite his fate. No longer the one-dimensional pervert of the novel, he'll use his future knowledge to manipulate heroes, seduce heroines, and rise from disposable villain to the true mastermind of this world.The system grants him power through every relationship he builds—but can this calculating reincarnator use his second chance to avoid his predetermined death and become the ultimate Harem King? One thing's certain: this story won't follow the original script.

An Individual from Earth finds themselves in the Shinobi World, equipped with a Scientific System. From that moment, he delved into scientific research far ahead of its time.

Su Wan is a Realm Destroyer. She shuttles to different time-spaces using the identity of the “Cannon Fodder Ex-Girlfriend”, dedicated to plotting how to happily tear apart the male protagonist and the female protagonist. –There’s no such thing as protagonists who can’t be torn apart, only Ex-Girlfriends who don’t work hard enough~

- Description from Novelupdates

Three reincarnations. Fourth life.

She was chosen to grow up as the Child of Fate; but when the real Child of Fate appeared, she was sacrificed for that child.

In the second life, she was abused.

In her third life, she lived as a beggar.

“This country is not safe. Let’s defect!”

LeBlaine chooses to be re-born into a new family to defect. The family she chooses is…

… the family of the future biggest villains in the Kingdom.

“Let’s try to get along until the time of my exile!” is what she tried to do. But what happened was…?

“My daughter is the cutest IN THE WORLD!”

“Give me that building, I can use it as my sister’s bathroom.”

“Don’t worry, LeBlaine asked me not to hit you. Not to not kill you.”

“WHO, WHO MADE MY SISTER CRY?!”