My Vampire System (WN) - Chapter 1453: A different evolution

With a marriage contract forcefully done, he married her, and all she could do was comply, and resent him deeply for that and for all the following misunderstandings they faced.
However, it was already too late when she understood she actually loved him.

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

Reach the peak of immortal cultivation and become able to run amok without fear! Use the power of martial arts to rule the world and defeat heroes! The weather changes at the whim and wave of a palm. He who cultivates both immortal techniques and martial arts, who could possibly defeat him! Xiao Chen is a shut-in who purchased a ‘Compendium of Cultivation’. Soon after, he crossed over into the Tianwu World, a world ruled by martial arts. He then refined pills, drew talismans, practiced formations, crafted weapons and cultivated the Azure Dragon Martial Soul that had not been seen for thousands of years. This is a story that tells of an exciting and magnificent legend!

A class full of idols and beautiful people are sent to another world. However there is one guy who is ugly, fat and smells… our protagonist. This is his comedic story of evolution and the slow building of his harem. The first heroine is a gorilla.