Arifureta Shokugyou de Sekai Saikyou (WN) - Chapter 449

Gu Mingxi and Pang Qian were next-door neighbors, classmates, and deskmates. From year-to-year, even when the class seating was rearranged, they would still be deskmates. They grew up together like a pair of brother and sisters despite having different parents; if it was someone else, then their parents would probably have already arranged their wedding. However, Gu Mingxi was different.

A High School Boy without friends, Odamori Tooru reincarnated into a Fantasy World after a bus accident on a School Field Trip. The job that was drawn 『Slavemancer』a Cheat occupation that dominates the minds of other.

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

Amid the steam of the industrial revolution, mysteries surge beneath the surface. Cults and secret societies seek the extraordinary in the shadows, while hidden gods gaze upon humanity from the heavens.Forbidden knowledge, sacrificial rituals, and forgotten histories—mystery is everywhere.Dorothy, unexpectedly transported to this increasingly bizarre world, discovers that to survive and move forward, she must adhere to one principle:Knowledge is power.And forbidden knowledge?That’s an even greater power!