MTL - I, Luffy, Awaken the Sun God on the Top - Chapter 11

At the end of the story, I found myself in the body of a hidden villain, betraying the heroines. Since I’m not particularly concerned about the end of the world, I’m calmly waiting for the finale… “You’re the only one who truly appreciated my painting of the boa.” “When I make plans to meet you at four, my heart starts racing at three... is this what they call being tamed?” For some reason, the heroines are starting to take an interest in me.

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

Ning Yechen used to be the Demon Lord. He singlehandedly took over the Demon Realm and attacked the Heavenly Realm. His name preceded him throughout the Six Realms. He got tired of fighting, so he quietly went into seclusion and became a happy hermit.One night, an Empress from the Heavenly Realm fell into the Mortal Realm after someone drugged her with an aphrodisiac. She inadvertently fell into his room, and they made out. After the deed, the Empress quietly left. Just when he thought he would never see her again, she showed up in front of him ten years later, bringing a child, saying it was his daughter and demanding accountability from him! “She’s your daughter. You have to be responsible for us!” Ning Yechen was stunned!

“But he is a good man,” she argued to see his eyes narrow at her words.