God of Music - Chapter 366

There was a woman. Born as an illegitimate child and raised under the strict control of the queen, her world was as small as a well.

There was a man. He was forced to marry a woman who was his brother’s political marriage partner. His world, which was infinitely wide, became smaller.

The woman’s original sin, and the man’s resentment. “I should have just died instead…”

A teenager named Evan Mason was reincarnated into the magical world of Harry Potter and goes to school at Hogwarts!
With only his knowledge of the future and great talent for magic, he takes the path towards the top of the magic world, only to realize that ever step he took, changed everything!

- Description from Novelupdates

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

As a precocious child, Lycoris suffers from a strange sense of deja vu. On the day her father told her about her fiancé, she realizes that her fiancé was a character from an otome game she once played in a previous life.