MTL - The Era of Hard Work - Chapter 454 vicious man

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

When 18-year-old Kyle Conner arrives at his aunt's for a summer holiday, he expects relaxation and freedom. Instead, his life is forever altered when he crosses paths with Lilith, the demon of lust and second-most powerful entity in the underworld.Forced into a dark pact, Kyle is transformed into a demon and gifted with a mysterious system that promises immense power. But this newfound strength comes with a deadly price: Kyle must hide his true nature and navigate the treacherous world of demons, all while being hunted by Lucifer and other malevolent forces.As Kyle struggles to control his newfound powers and unravel the secrets of the system, he discovers his ultimate goal: to overthrow Lucifer and bring about a new era of peace. But with the forces of darkness closing in, Kyle must confront the darkness within himself and make impossible choices to survive.Will Kyle be able to master his demonic powers, outwit his enemies, and fulfill his destiny? Or will the weight of his newfound responsibilities consume him, dooming humanity to eternal darkness?

In a world where its inhabitants can destroy a city wall single-handedly, the empress has a kirin as her pet, and the imperial palace of Great Xia has a pool containing a dragon. There is also a Sword Mountain where spirit swords occasionally leave in search of a master .

This is a cliché story about two young people saving the world.