A Mastermind? No, I'm just the Live-In Son-in-Law - Chapter 88: Sincerity

What happens when a history teacher dies and becomes a prince in another world? Of course, he becomes the greatest emperor!He will use all of his family's resources for his own benefit, conquer the world, and... beautiful women! Ahem. This is a novel full of intrigue where he will get what he wants, build his own empire, and finally protect his loved ones.He is a great leader to those he cares about, but a ruthless tyrant to his enemies. In this world of magic and mystery, he will not stop until he reaches the top.But what will he have to sacrifice for victory?

Under the vast immortal sky, the brilliance of an era is nothing but fireworks blooming at the fingertips.

Overlooking the earth, for thousands of years, life and death, where are they all? The Immortal Gate, the Dynasty, and the Supreme Holy Land are all just a handful of loess under the Immortal Vault.

A thousand years of splendor, and a smash into ashes.

Cinders sprout in the depths of the ruins, and you and I strive to be the trees that reach the sky.

What the hell is on the other side of the Immortal Firmament?

- Description from novelbuddy

What happens when a scientist from a futuristic world reincarnates in a World of Magic and Knights? An awesome MC is what happens! A scientist’s goal is to explore the secrets of the universe, and this is exactly what Leylin sets out to do when he is reincarnated. Dark, cold and calculating, he makes use of all his resources as he sets off on his adventures to meet his goal. Face? Who needs that… Hmmm… that guy seems too powerful for me to take on now… I better keep a low profile for now. You want me to help you? Sure… but what benefit can I get out of it? Nothing? Bye. Hmmm… that guy looks like he might cause me problems in the future. Should I let him off for now and let him grow into someone that can threaten me….. Nahhh. *kill*-

Alternative: Leylin is transported from an advanced technological era into a medieval world— except there’s magic. Equipped with “only” his quick wits and an A.I. chip fused to his soul, he sets out to become the most powerful magus the world has ever known. In a land divided into the Light and Dark Magi, the weak can either be cattle or disposable slaves. Only the strong can determine their lives, and only they have the luxury for virtue. Yet strength is only a tool for Leylin, like any other. His goal, in the end, is his own.

Seventeen-year-old Grayson has endured a harrowing childhood, leaving him with a dark and twisted philosophy. Driven by this painful doctrine, he imposes his skewed beliefs on everyone and everything around him. His malevolent actions draw the attention of an ancient evil, an entity wrapped in darkness and legend. This being sees in Grayson the potential to carry on its legacy.As the ancient evil begins to mold Grayson for a future drenched in darkness, he finds himself drawn deeper into a web of manipulation and control. Questioning whether he has the strength to defy the fate that has been thrust upon him.Theós, an ancient deity whose origins are lost to time, rules with an iron grip, instilling fear and absolute control over those who dare challenge him.“If it is not within Theós' plan, it cannot be done!”