The Simple Life of Killing Demons - Chapter 1Book 2:

Back in 1998, an ordinary person who has been through, tired, cried, and fought, hopes to run down-to-earth and keep up with the trend of the times.

- Description from novelbuddy

Born as twins, but Mu Qiqi was left suffering every torment and became the greatest scapegoat in history only because she was not a better actress than her sister!

Yang Yang starved to death once, so after rebirth, he had only one wish: food and clothing.

However, in the blink of an eye, Yang Yang heard his uncle say that he had to cut open his stomach to take out the eggs.

Yang Yang: … I advise you to be kind.

In order to protect himself, Yang Yang found out the identity of the father from the birth center, and he embarked on a road of no return.

Yang Yang: Duke, your family is in my hand.

A young unmarried duke: ? ? ?

- Description from Novelupdates

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.