Itai no wa Iya nanode Bōgyo-Ryoku ni Kyokufuri Shitai to Omoimasu - Chapter 10

Yuka, reborn as the daughter of the universe's richest man, tries to live a simple life. She gets a big shock when she has to join Union University of the Alliance because of government rules.In university, Yuka picks an easy major, hoping to keep a low profile. But her plan doesn't work. She keeps facing tough situations that show off her smart mind and strong skills. Yuka tries hard to live normally but keeps getting pulled into extraordinary accidents.This is the story about how Yuka grows. It's about her trying to hide her real identity while dealing with a world that always challenges her.

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

Once through the pirates, Lu En became the son of Monkey d Dragon, a grandfather named Monkey d Karp, and an unreliable and neurotic younger brother named Luffy.

Fortunately, the ghost back system is activated!

The completion of the ghost back is 10%, and the training effect is increased by 100 times!

The completion of the ghost back is 20%, and the training effect is increased by 1000 times!

…

One day, Lu En, a ghost-backed master, appeared in front of Luffy who was shouting to go to sea, and made Luffy cry on the spot.

Luffy: “The pirates in the sea are all monsters like my brother? I don’t want to go out to sea!”

Garp: “For a long time, the two boys, Long and Luffy, with small arms and calves, I really doubt that they are not my sons and grandsons. Like Lu En, they are the grandsons of the old man!”

Warring States: “The strongest creature in the sea, land and air is Kaido? No, it’s Lu En!”

- Description from novelbuddy

She was originally the king of the dark mercenary world, killing, plundering, and looking down on the world; once reborn, she became a powerful family that shocked the continent, the “Ninth Young Master of Waste” of the Beiting family;

From then on, the elegance of the world, shake hands;

Belonging to ancient monsters, possessing a magical space, practicing heaven-defying skills, killing the sky, killing the gods, and doing whatever they want;

Cool and handsome, domineering and arrogant, leading the world to compete;

In this article, the male and female protagonists are double C, male strong + female strong, and the ending is one-on-one;

- Description from novelbuddy