Dominion's End - Volume 4, Chapter 9: In This Life, We Both Are Doing Swell, Part Two

It’s a story about a man who got transported into a novel and possessed a slum boy. He met a noble girl and served her as a butler for 13 Years. Now the girl has already fallen from her noble life and lives in an abandoned mansion with paralyzed legs. Why did she become like that? Of course because she is the villainess in the novel.

The formless ancient world was infested with despicable demons. They hunted and feasted on mankind, keeping the human civilization constantly in a weak and suppressed state.

During the first known year, a magical mountain descended into the world from the realm of the Gods. Carved on this enormous mountain was a message: ‘Heaven Prevails’…

After the Grand Descent, a name that was given to the descending of the mountain, the Three Great Sages made their ways to Mystic Mountain where they learned to harvest what we now call magic, establishing the Mystic Cults and eighty-one sacred shrines to help aid mankind with the cult’s mystic powers against the eternal fight to the death with demons.

- Description from Novelupdates

Although Leng Ruoxue is born mentally challenged, she is the most beloved granddaughter of the number one general in the Eastern Lake Nation. She is despised by her fiancé and schemed against by her love rival. However, she is reborn as a powerful soul. This is a fantasy world, and also a world where the strong are respected. Cultivation, alchemy, weapon refinement, beast taming—the once foolish young miss has transformed into a stunning genius. Pill refinement and weapon refinement are all child's play. Heaven Grade medicinal pill? Even my pets won't turn an eye to it. Heavenly Treasure? I have the space to grow my own. Sacred artifact? Sorry, that's too low a level. I only know how to refine divine artifacts. Beast taming? My beasts deliver themselves to my doorstep.

A skilled but unfortunate modern-day assassin was killed in a freak accident. However, he soon found himself summoned to another world by an evil wizard, who had him possess the body of a boy as an experiment. After successfully planning the evil wizard’s downfall, he used the wizard’s body as a springboard to gain influence and power in his new world.

- Description from Novelupdates