I Am a Rune Engraver, Carrying a Knife Makes Perfect Sense - Chapter 50 - The Capital is Full of Tunnels

My name is Joo In-gong. The name that my parents gave me meant ‘protagonist’ of the world. Really?

After blacking out at a class reunion, Li Yuan awakens in a brutal world reminiscent of ancient China. Famines rage, human life is cheap, and the specter of war looms at every corner. Worse still, the eerie rumors of monsters lurking deep in the forests and things that go bump in the night prove all too real.Now scraping by as a humble hunter in a remote village, Li Yuan must also watch over a woman entrusted to his care. Although he’s blessed with a mysterious status window, he’s still just a leaf on the wind—easily blown astray by the sweeping storms of change. Join him as he struggles to navigate political upheavals and unforeseen perils, striving to forge his own destiny as history unfolds around him.Official: Li Yuan crosses over into a martial world where demons and ghosts lie dormant, becoming an ordinary hunter struggling to survive. It’s only after he takes a wife that he discovers a status window. As the stars shift and ages pass, though seas dry and lands change, he remains steadfast and unchanging.

Legend says, that there is a great demon, who is the human kind’s public enemy. He is the galaxy federations’ nightmare as he wanted to conquer the whole universe. On the first day, he completely took out the human fleet, plunging them into disorder. On the second day, he declared that he will wipe out the whole federation. On the third day, he declared——that the hero who shot him in their previous battle must marry him, or else, he will destroy everything.

The galaxy federation president and the council members had a long meeting after that. They decided to dispatch a soldier, Wu Xing Yun, and marries him off to the arrogant demon. Wu Xing Yun was once a hero who fought for the nebula, and henceforth, he was tasked—— for the sake human race and the universe’s peace, to eliminate mistresses, settle his matters with the mother-in-law, and fix the man’s crooked ways.

Wu Xing Yun was very perplexed when he asked his commanding officer: “Sir, why did it have to be this way?”

Commanding Officer: “Soldier, bear in mind, that this mission of yours, is for the sake of the universe and mankind’s happiness. You must hold on to your husband, and fight other mistresses! Do you have the confidence to accomplish this task?”

Wu Xing Yun, stood straight, saluted, and instinctively replied: “Sir, yes sir! I will accomplish this task!”

- Description from Novelupdates

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.