The Strongest Conquest System - Chapter 487: The Old Duke

Su Wan is a Realm Destroyer. She shuttles to different time-spaces using the identity of the “Cannon Fodder Ex-Girlfriend”, dedicated to plotting how to happily tear apart the male protagonist and the female protagonist. –There’s no such thing as protagonists who can’t be torn apart, only Ex-Girlfriends who don’t work hard enough~

- Description from Novelupdates

Henry is a university graduate who happens to be working as a hotel receptionist, though with big dreams of being more than that. All these change for good one day when he finds a way of cracking a very sophisticated technological system, which ultimately empowers him to formulate and develop leading-edge inventions from his bedroom.With a determined mind not only to conquer the market but also to move out of his gray life, Henry starts into his journey of fame by introducing a number of radical technologies that capture the interest of the whole world and hold it.

King Grey has unrivaled strength, wealth, and prestige in a world governed by martial ability. However, solitude lingers closely behind those with great power. Beneath the glamorous exterior of a powerful king lurks the shell of man, devoid of purpose and will. 

Reincarnated into a new world filled with magic and monsters, the king has a second chance to relive his life. Correcting the mistakes of his past will not be his only challenge, however. Underneath the peace and prosperity of the new world is an undercurrent threatening to destroy everything he has worked for, questioning his role and reason for being born again. 

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.