MTL - Yin Yang Eye GunGun’s Marriage Contract - Chapter 19 Flushing into a material

Reborn as a sister of a villain with no blood or tears in a war-fiction novel. Anyway, that guy, who plays ‘my brother’ role, is a villain who will be sealed by the Main Lead after losing the war. So I just need to pretend to be his little sister until he disappears. No, at least that’s how I think … ‘Something in your right hand, is that the main lead’s head?’ My brother won the war. *** “What’s with the suitcase?” “Yes?” At the tip of Dietrich’s long finger, there was a package that I had wrapped up as soon as he left for the battlefield. “I asked what it is.” “It’s, It’s a travel bag, brother.” “Travel? Alone?” Dietrich’s dark eyes glistened. The man who had just returned from victory had a strange smell of blood from mu*der. “Will you leave me?”

He rose from abjection and achieved eternity in glory.
He embraced the prettiest beauties and killed the strongest opponents.
He was able to shift the clouds into rain and cover the sky with one hand.
He could overrun the entire world and go anywhere as he pleased.
He pacified wars and held the world in awe.
He was matchless in the world.
However, his hair turned white overnight for his beloved woman and he was on the verge of death.
He was surrounded by enemies who were trying to take his life.
He struggled his way to become mighty and fought for everything he cherished.
For this age, he was the only king of the Dark World.
His name was a byword for might.
As a man living in the world, his only ideal was to pursue brilliance.

- Description from Novelupdates

The story is about a a hitman, Who dies because of his own recklessness and transmigrates into a game he used to play after his retirement as a hitman.I'm not gonna spoil any further, but i might answer few of your questions.Is MC overpowered?Nope, he'll become strong over time and all battle he'll fight will be because of his effort and techniques.Is there magic and adventure?Yes! It have both magic like normal isekai with adventure and fighting with monsters and many other things. There are other important things like “Essence Stone” But let's talk about it in the chapters.There will be harem?Not really, He will be in contact with many beautiful female and males but one waifu but i haven't decided yet.All i can say is, give it a try, I'll try my best to make it worth your time.

Li Yi accidentally obtained a black science and technology library, which contains countless books of the inheritance of high-tech civilization and records countless knowledge.

There are thousands of bells in the book, there is a golden house in the book, there are many horses in the book, and there are Yan Ruyu in the book.

Li Yi has completely turned into a bookworm, learning all kinds of knowledge from the library, grand unified theory, particle Tebo theory, …, acquiring various black technologies, superconducting materials, super batteries, intelligent algorithms, … .

- Description from novelbuddy