Let Me Game in Peace (WN) - Chapter 1027: Battle of Terror Creatures

The word defeat did not exist for Wei Congying in his relationships.

But the biggest joke was after the prodigal son returned and realized he was someone else’s stand-in.

Three years after breaking up, while sitting in a fast food place in the Isle of Mann, he saw her and discovered an something even more laughable…

He was still in love with this heartless person.

- Description from Novelupdates

This is an alternate history. Decades after the fall of the Eastern Jin Dynasty, the world is still in chaos, although there is hope for reunification.

A man who was once called the world’s strongest agent ended up becoming a teacher after his retirement, to train a new generation of agents. After many years of training his disciples, he was killed at the age of 60 by a secret organization’s ruse and was reincarnated in another world with his memories intact. Though he was surprised by the existence of magic and the strange species in that world, he quickly adapted to his condition as a newborn and took advantage of it. He acquired special magic and gained a massive amount of strength thanks to his rigorous discipline, in order to reach his goal: Resume his career as a teacher which he left halfway through in his previous life. This is the story of a man, who, based on the memories and the experiences of his previous life, became a teacher who travels through the world with his students.