The Hidden King's Stolen Wife - Chapter 31: A Thousand Jewels

In the year 54 of the Konoha Calendar, two super geniuses appeared in the Konoha. One is named Uchiha Itachi, and the other is named Akihara Kagura. One is a tool of the village, willing to sacrifice everything for Konoha, except for his brother Uchiha Sasuke; the other claims to be a tool of the village, also willing to sacrifice everything for Konoha, including Uchiha Itachi's brother, Uchiha Sasuke.

“Please, I implore you to save the world.” This is what a goddess in white says to me in a pure-white space. Such is the standard line that suggests the game is about to begin. Please say this stirring line to boys and girls with sparkling eyes! It’s wrong to direct it to someone like me, who’s exhausted from job hunting! When I declined her politely, she flew into a fit of tears; when I agreed to assist her on small tasks out of reflex, she proclaimed: “it’ll be fine if you just help in the Starting-Village Arc. Please guide the Hero!” Then she tossed me into another world. No, this is a world modeled after a game that this gamer goddess likes…

Anger. Pain. Desolation.

He is a young man without a spirit root. It is believed that this denies him the chance at cultivation. However, a mysterious lady imparts a Supreme Demon Classic to him and from then on, he starts his path of cultivation.
He undergoes a total transformation to emerge as the most fearsome and powerful fiendish demon in his era, that even immortals and fiends are fearful of him, and saints are at his beck and call.
Mastering the Supreme Demon Classic is the turning point in his life. He is able to unleash his immense and divine power from within, illuminating the entire universe!