Fortunate Eighties: The Bewitching Female Rival Who Tamed Her Husband with Skill - Chapter 106 - 136 was included

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

A side story series featuring the girls of Kyoukai Senjou no Horizon.

His name was Brayden Neal, and he was an ordinary citizen. At eighteen years old, he was bestowed the title of a king!

After ten years of fighting in the northern borders outside the kingdom, he finally returned home. He swore to kill three people the moment he arrived at the capital…

Freshman student Yang Dingtian possesses the Nine Yang Body, found only 1 in million. His Yang Fire is incomparably vigorous and thus, he cannot be near a female’s charms for his entire life. On the night of his 19th birthday, he decided to bid farewell to his virgin life. After stealing and tasting the forbidden fruit, he spontaneously combusted as the result!

In death he crossed over to another world; a world that held respect for Martial Power. His, originally, catastrophic Nine Yang Body was the Nine Yang Body that couldn’t be seen in a millennium! He was saved by a mysterious old man when he was at his last moments and the old man received him for a disciple, then betrothed his daughter to him. Thus, in this odd way, Yang Dingtian became the successor of the largest clan under Heaven, and became the number-one-beauty-under-heaven’s fiance.

- Description from Novelupdates