The Extra's Reincarnation - Chapter 137

She, a 21st century mercenary queen, had crossed over into a tragically betrayed body of a waste. Waste? She will show them what it means to be a waste! Betrayed? With the Ancient Manual in her hands, she will astonish all the despicable men and cheap women!

Wait! Didn’t everyone say that she was an evil woman which everyone feared? Why is his Third Highness, full of mystery and charisma, so interested in her?

- Description from Novelupdates

At the beginning of the universe, there was only chaos. Chaos gave birth to a world, accumulating into Black and White and the five elements (also known as the Origin Elements), creating the world's laws and the order of heaven and earth.

This world was called the Origin world, where the Original beings born out of chaos reigned. They created orders, creatures, and numerous worlds where they reigned as Supreme beings until a calamity befell them and destroyed the Original world alongside numerous worlds.

Two billion years have passed since then. In a small world somewhere, a baby was born carrying an unusual past.

He Lang died by his own hands for the sake of his imperial younger brother’s ambition, whom he loved. He was offered to be reborn in exchange for giving up his past romantic feelings. Reborn without the burden of his romantic feelings, he brings with him a manual to new worlds. He wholeheartedly followed the instructions of the manual to complete the tasks, not knowing that the originally slag gong was blackening…
He pleaded to his affectionate Emperor brother to release him, he pleaded to the paranoid prisoner next door, but until the end he remained baffled.
In the end, he discovered that the full name of the manual was – “Slag Shou Cultivating Manual”
Σ (っ ° ° °;) っ!

- Description from Novelupdates

Intellectual Villages are old fashioned rural villages recreated with cutting edge technology. Those villages attract the Japanese monsters known as Youkai.

The high school boy Jinnai Shinobu lives in one of those villages and has a Zashiki Warashi living in his house. He tends to run across Youkai with unnerving frequency and this often leads to trouble for him.