Gekitotsu no Hexennacht - Volume 1, Chapter 1: Witch in the City

Ling Xiao was a powerful martial expert who fell in battle and was unexpectedly transmigrated into another world. He began life anew in the body of a boy with the same name, a fallen genius of the Ling Family whose cultivation had been crippled in a surprise attack, and son to a father who had also suspiciously been crippled under similar circumstances. Armed with knowledge from his previous life, Ling Xiao aim to restore his strength and establish his place at the top of this new world

- Description from Novelupdates

Born with a silver in her mouth, she suffered a fatal betrayal. Not only did she lose her family property, but also her parents died a tragic death. Reborn, she won another chance and some superpower. This time, she would take back her everything and repay the last man she wanted to see in her previous life. He was the youngest major general in history and the most charming one among the presidential candidates. Now that she wanted to make up for it, he would never let her go.

He was the youngest guru of martial arts as well as the perfect Mr. McDreamy of the most girls. He had mysterious absolute touch, clear-sighted observation ability and various outstanding talents.

Good Looks: Check!
OP Skills: Check!
Face Slapping: Check!
PP Size: Check!

Lucien was more than ready to embark in his new adventure to save a dying world from destruction as part of the Heaven's Gate Project.

However, just as he was about to be sent to the world that he was about to save, an accident happened, which forced his Patron God, the God of Gamblers, to take another gamble in order to preserve his chosen candidate's life.

Lucien, who's new identity was named Lux, found himself in a world where darkness could be light, and light could be dark. A world where morality was but a thin line from depravity, and a happy ending could only be gained, by facing the world and slapping it with a Legion of the Undying.