MTL - I’ve Transmigrated Into This Movie Before - Chapter 54 First love forever

One night a mysterious and unexplained phenomenon occurs in the nine provinces. Five years later Chu Feng, a regular outer disciple of the Azure Dragon school, awakens one of the mysterious nine lightning beasts. And discovers an egg sealed inside him.

From there we follow Chu Feng as he crosses the continent, beating up strongest senior brothers, raiding tombs, destroying sects and of course as he conquers beauties.

Satou Shiki a Japan present-day university student suddenly one day he got attacked by a slasher when he open his eyes he was already transferred to another world’s labyrinth city. In that another world he who was awakened to do a lot of “things”.

For the large sum of money to help her husband, she chose to be a surrogate mother covertly. Her sweetheart was out of trouble, but she became the woman of loose morals in his eyes. Misunderstanding, disappointment and sadness forced her to divorce the man she loved from the childhood.

When she was determined to start new life, another man burst into her life. “You are my baby’s mommy and you are my wife!” A big surprise hit her that her baby’s Daddy, the man she surrogated for, fell in love with her at his first sight.

His deep love convinced her to believe the affection of love again. Unexpectedly, her ex-husband returned to beg her recombination. One was her childhood sweetheart, and the other was the man who loved her and gave her hope for a new life……Facing the two men, what is her choice?
 

- 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.