Killed For 100 Years in Hueco Mundo, Aizen Invited Me To Soul Society! - Chapter 1 - 00: Centenary Of Hueco Mundo

Lin Xiao was an orphan who strived to get stronger while living with his sickly younger brother in an unnamed small village.

Jiang Chen, son of the Heavenly Emperor, unexpectedly reincarnated into the body of a despised young noble, thus embarking on the path of the underdog trouncing all commoners. No one has the right to call himself a genius in front of Jiang Chen, as no one has a better understanding of the heavens than the son of the Heavenly Emperor. “Genius? He who adheres to me shall ascend. Those who oppose me can find solace in hell!’

The notorious imperial court lackey and the meritorious military general were well-known for their mutual dislike, a pair of arch-enemies set in stone. Who could have foreseen the unexpected change in the winds of heaven: the general injured on the battlefield, both legs disabled, and even forced by the emperor to marry his nemesis.  

With one marriage edict, two people with mutual hostility are forced to marry and live under the same roof. Yet after these long days together, they come to the realization that this fellow is not truly devoid of any saving grace/unattainable and high out of reach.

- Description from Novelupdates

This is the era where people prioritize science and Martial Dao. After the great disaster, the human race discovered the Ancient Zenith civilization. They entered the Age of Great Cultivation and began their journey to colonize the Kunlun Realm!