MTL - Urban Carefree Immortal Emperor - Chapter 274 Reverse, lore!

Because her appearance was not breathtaking, the Emperor breaks off their engagement and bestows her instead to the bloodthirsty, ruthless, and cold-blooded Second Prince (Wang Ye).

On her wedding night comes endless humiliation, the genuine Princess Consort becoming a deserted women. A foolish woman before rebirth, she no longer expects his love. In this world, she must possess enough talent to awe those around her, carrying herself with composure and articulating with beautiful diction, override above the nine night.

- Description from Novelupdates

She was originally the young miss of the Marquis Estate, but became a peasant girl due to a mixed-up at birth.

From the outcast of the imperial family to the emperor, Wei Chongrong’s path to the throne took thirty years.

In his previous life, everyone thought that he shouldn’t exist.

Only his youngest uncle was good to him, so he went through fire and water for him.

But what he ended up waiting for was the poisoned wine poured for him by the youngest uncle’s own hands.

Starting over, Wei Chongrong, who is familiar with the future, finds that the road ahead is still bumpy.

The battle that is bound to be lost is about to happen, and the scourge of witchcraft is close at hand.

What can he do to save the Eastern Palace and the imperial family, and to save Jun Hua, to whom he is indebted for a lifetime?

- Description from Novelupdates

This legend tells the tale of the protagonist, Kuroki summoned to protect the demon king from the hero.

Kuroki, unbeknownst to him, suddenly came to another world. He was summoned by the demon king, Modes. The territory which the demon king overrules was in the midst of being destroyed because of the hero. He had no choice but to bow before Kuroki.

“Please save us, Savior Dono!”

Kuroki nodded, deciding to save the demon king due to an unexpected turn of event.