The World of Otome Games is Tough For Mobs - Side Story: Nightmare Ulysses-chan

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

Yang Yi crossed over the world with a storage space with him. He ended up in some desolate wilderness populated by flying beasts and dangerous predators and also crawling poisonous bugs and snakes. To prevent getting bitten in the ass by venomous bugs when going to the toilet, let the great infrastructure begins –
Our goals are:
Eat well till full stomach.
Having clothes to wear but also being good looking.
To have a house that could cover all seasons.
Roads that leads to every place; develop agriculture, industry and commerce together.
No shortage of both material and spiritual needs.
He was DETERMINED to build a safe, comfortable and prosperous modern city in the wild world together with the native tribe with max efforts.

- Description from Novelupdates

Reborn into a failing noble family, Liu Xingchang awakens in a weakened teenage body, surrounded by humiliation and betrayal. Once the revered Sword God of the Northern Polar Heaven Domain, he now faces ridicule from his former lover, Yu Qiuer, who has abandoned him for a rival, and scorn from the very man daring to tread on his legacy.Though his power has diminished to a mere third-grade cultivation, Liu’s indomitable spirit drives him to reclaim his path to supremacy. When he fatally strikes his foe amidst the disbelieving crowd, even the noble Princess Qingyuan is drawn to this fallen “”coward’s”” defiant strength.Can Liu Xingchang resurrect his family’s honor, ascend to the Divine Realm, and turn the tables on those who scorned him?