Isekai Maou to Shoukan Shoujo Dorei Majutsu - Volume 8 Chapter 4

Forget about moving to the other side of the world and starting over.The Apocalypse is here!As the only survivor of the Tutorial Quest in his area, Elijah awakens the Class of “Depraved Hero”, an ominous-sounding Class with a Legendary Rank!Additionally, because of the insane difficulty as well as his Clear Rank, he gains the Skills that, according to the mysterious figure that is the Administrator, he needs most.[You have Developed the Skill “Absolute Authority[A]”.][You have Developed the Skill “Slave Mark[C]”.]

In the foreign world, the martial artists dominate the world and the sword of the emperor controls the fate of hundreds of millions of lives! Long Yu, the number one killer on Earth, after dying, takes rebirth in this new world in an aristocratic family of martial artists but faces rejection because he is unable to practice martial arts.

- Description from Novelupdates

He, since childhood, had followed the Foreigner to practice the Defying Heaven Art, entering the most secretive special forces and becoming a fearsome assassin that made others tremble at the mere mention of his name. After a single failure, he took early retirement, but he ended up as the personal bodyguard for a rich heiress, a school beauty. Accidentally provoking some mysterious Cultivators, he gradually unveiled a hidden world of Cultivation beyond the mortal realm...