The Sword and Heir of Shadows - Chapter 45: Full of uncertainties.

Reborn into her younger years, she's determined to rewrite her fate.This time, she'll earn her own fortune, buy that dream villa, outsmart every scheming character, and never hesitate to protect herself—even if it means hardening her heart.Her (blinking in disbelief):“Wait… does this mean I'm now on the same level as a rich tycoon?”Him (smirking):“Not quite. You're already standing on the tycoon's foot.”

Masterpieces such as 'The Divine Comedy', 'The Theory of Evolution', 'Encyclopaedia Britannica', 'The Theory of Relativity'...Born in the history of human civilization, possess mysterious and magical powers in another world!Original sin, biological evolution, mastery of all arts...By reading the secret tomes, one can gain a variety of powers!The only trouble for the people of the other world is that they find it difficult to understand the texts from Earth.At this time, there comes a librarian from Earth...

The end of the world is coming, the world has undergone great changes, and everything has changed. Plants, animals, and even insects, as long as there are living things, have mutated.
Become more powerful, and even evolved supernatural abilities, such as chickens and ducks that can fly to the sky, such as cats and dogs that can breathe fire.
But only humans, without any obvious changes, seem to have fallen from the top of the food chain to the bottom of the food chain overnight.
Any creature that can open its mouth to eat can treat humans as food.
But fortunately, this world has not completely killed humans. Gradually, humans discovered that they had the ability to cultivate compatibility with other creatures.
As long as it has a high degree of compatibility with some powerful mutant creatures, it can be used for its own use to achieve the purpose of protecting itself.
Fang He is a person who is very compatible with mutant animals, but it is also because of his ability that he has changed from the strongest to the stupidest.
Fang He, who was reborn, said, “Hmph, this time…”

- Description from novelbuddy

“I will have my vengeance, in this life, or the next!”Albedo died alone and depressed and was reborn in a Novel he had been reading. However, instead of becoming the Protagonist or Antagonist, he becomes Albedo Neverwinter, an Extra he couldn't even recall from the Novel.However, the cruelty of life didn't change even after rebirth, and his new family was ripped away from him, leaving him with nothing but scars as reminders of the gruesome fate his family faced.Promising to get his revenge, watch as Albedo, alongside his System, his tactical mind and scarce but valuable future knowledge, rises up the ranks and ascends the pyramid of power.[ OP MC, System, Harem, Romance ][ Yeah there will be Smut, but it won't dominate the Novel ]