MTL - Pen Down A Marriage - Chapter 2

He became a teacher at the best magic academy in the empire.
….For being mistaken for someone else.

In a certain world, there was someone who excelled in magic combat, people called him 『Sage』. Seeking the strongest combat art, he devoted himself to research every magic and combat arts in existence. And the conclusion he arrived at was very cruel, 『My body is not fit for magic combat』. Yet he didn’t give up. He sealed his own soul with a magic art, and was reborn in a far-off future. And the magic theory in the completely changed world he saw there was of unbelievably low level.

Eight hundred years ago, Xie Lian was the Crown Prince of the Xian Le kingdom. He was beloved by his citizens and was considered the darling of the world. He ascended to the Heavens at a young age; however, due to unfortunate circumstances, was quickly banished back to the mortal realm. Years later, he ascends again–only to be banished again a few minutes after his ascension.

Now, eight hundred years later, Xie Lian ascends to the Heavens for the third time as the laughing stock among all three realms. On his first task as a god thrice ascended, he meets a mysterious demon who rules the ghosts and terrifies the Heavens, yet, unbeknownst to Xie Lian, this demon king has been paying attention to him for a very, very long time.

- Description from Novelupdates

For three years, Finn Taylor is utterly humiliated. He has endured everything from physical beatings to verbal abuse. For three long years, he has gone by only one identity—the useless matrilocal son-in-law of the Larson family. But this life as he knows it is about to be turned upside-down as he reclaims his position as the head of Peregrine Hall.