Hagakure Sakura Does Not Lament - Chapter 73

Through a mysterious portal, Chen Jin arrived at this strange place – a post-apocalyptic world where civilization had been destroyed.

Consequently, he found –

A piece of metal scrap
A robot trash collector
A battleground
A city
A ton and more of gold
A copy of high-tech documents
A…
In short, Chen Jin found a planet.

- Description from Novelupdates

The MC (Minato) is a college student who died in a plane crash and was reincarnated in a fantasy world. He was raised alone in the wilderness by his succubus mother, and now he tries to make his way as an adventurer.

She was an illegitimate daughter in a wealthy family, with a lowly status. By chance, she discovered that her ex-boyfriend had sold her out. In order to hide, she accidentally injured him and fled in a panic. From then on, they were bound by an inextricable bond...

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