Naruto: The Life Changer - Chapter 48 -:

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

To sum up in a sentence, *slag men **washing white daily, transmigrating to different worlds to wash white, and the goal is to become a good man!

Note:
*Slag men refer to men who play with women’s hearts aka scum.
**Washing white means to come clean, fix up your life.

- Description from Novelupdates

Three Days of Happiness is a novel by Sugaru Miaki, also known as Fafoo. It’s a rewritten version of the story originally posted to 2ch.

The premise of the story revolves around a shop where one can sell away the remaining years of their life, and the consequences of doing so.

“I Say A Little Prayer” is a short related story which was posted along with the novel’s release. It spoils some things about the main story, but nothing major.

On her wedding night, Jian Ran met Zhou Huai'an, the man rumored not to like women.After that, she was cautious and humble in front of Xu Zichuan every day.Until that night, when blood flowed and rain poured, she learned the truth.She collapsed in the pouring rain, hugging herself, laughing madly with tears streaming down her face.Then, she slowly bent her proud spine, trampling her dignity into the mud.In the end, when Jian Ran left, Xu Zichuan went mad.Zhou Huai'an kneeled on the ground, “Jian Ran, I was wrong. What must I do for you to return to my side?”