Villain: I Must NTR All The Hidden Bosses! - Chapter 15: Fragment Of Extremity.

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.

Kakashi has lived a sheltered life within the protective confines of a barrier, which shielded them from the dangers that lurk outside. Raised by his devoted mother, Ako, and loving sister, Tokah, he only know a world of happiness and joy. Living in a world where he thought nothing could go wrong.But when a group of men invades their home, everything changes. In the brutal assault, Kakashi witnesses his mother's tragic death, a moment that shatters his naive understanding of safety. While his sister manages to escape, Kakashi is captured and subjected to experiments designed to exploit his hidden powers.Years later, amidst the ruins of a collapsing facility, granting Kakashi a chance at freedom. Rescued by an academy dedicated to training gifted individuals, he discovers not only the extent of his abilities but also the resolve to seek vengeance against those who tore his family apart.Driven by the desire to reunite with Tokah and avenge his mother's murder, Kakashi embarks on a journey filled with action and self-discovery.As he navigates the treacherous underbelly of a world rife with superhuman conflicts, he must confront his own problems while mastering the very powers that once made him a target.

There’s the so called class transfer.

Among the high school students that were given cheat abilities, Kirishima Ran was given 『Underling Training』for some reason, a skill that can make a woman a slave.

Ran who was driven out by the kingdom using an absurd reason will make use of the given skill freely to take revenge on his classmates, release his desires (This is mainly the reason), and fight off the world’s system.

It’s a story of him using his wonderful skill making his classmates turn to an obedient cute and lewd slave.

Bai Yanliang, male, 23 years old, unmarried.Condition improving, good personality shaping, has met the discharge criteria.Today, discharged.