One Piece: Fist of the World - Chapter 45: Together!

A woman from ancient times falls in love with her soulmate.

In the current era, people are either normal or are with ‘special abilities’. Cases related to the latter are managed by the “National Anomaly Prevention and Control and Special Species Management Office”.
Qi Zheng Emperor Sheng Lingyuan was reawakened a thousand years later after he jumped off the fiery Red Lake. Xuan Ji, a newly transferred staff to the Reparations Division of the Deviant Control Office, finds himself having to clean up the mess of a revived tyrannical monarch. The two seemed to share something from the past, but unbeknownst to them, a big conspiracy is stirring right underneath their noses that could destroy the balance of the world.

- 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...

Sixty years after the global catastrophe, the Little Freeze Period ended, and the governments of the living regions began to collect land in the anarchic areas to be planned on a large scale, reorganized resources, and entered the recovery stage in an all-round way. These two decades are also called “golden Twenty years”.

This is a bright era in which new regions are rising one after another, politics is set up, capital is acting, careerists are everywhere, heroes are powerful, villains and grassroots are rising together! A young man rises up in troubled times with a full stomach of strategy, hides a tiger in his chest, and measures the world.

- Description from novelbuddy