The Last Incubus with The Vice and Valor System - Chapter 17: Amelia explains the world...

The little handsome son-in-law passed through a world as waste material and the husband of a wealthy family. But because of his lacking aptitude, the wealthy family had driven him out. So he worked hard and found a more powerful family’s thighs to hold onto. Soon enough, he became the strongest son-in-law and husband in history.

In this world, it was impossible to practice martial arts. It was futile so he might as well take advantage of his wife’s thighs and maintain a comfortable and leisure lifestyle.

He’ll train his wife to become the strongest and best person in the world.

“Whoever dares to provoke me, let my wife kill you!”

- Description from Novelupdates

This book is also known as: “How Programmers Turn a Crappy Game into a Timeless Classic with a Single BUG”Recently, the president of Nitiandang, Gu Fan, once again fell from grace due to a minor bug in his new game.As a top-notch designer in the industry, all of the games designed by Gu Fan have very distinct characteristics:At first, players felt that these games were monotonous, dull, and purely revolting garbage.However, once players discovered a major bug, the gameplay underwent a drastic transformation, rendering them sleep-deprived and unable to quit!So, players once again launched a major debate over “whether this is actually a bug or a game mechanic.”In response to this, Gu Fan clarified in an interview with all seriousness:“Hello everyone, I'm the game designer Gu Fan, but you can also call me by my English name: fan·gu (means rebel).”“I want to reiterate firmly that these so-called 'core gameplays' were not part of our company's original design—they are bugs! It's just that we didn't fix them because the players liked them!”

A Japanese salary man was reincarnated in a different world with swords and magic. He reincarnated into the family of a powerful noble. One day when he became twelve years old, he was suddenly summoned by his father.

「 I do not mind whether it is a woman in the town or a maid in our house, learn about women.」

Having gained the permission of his father, he uses his power as a noble to have his way with women.