Strongest Survival by Otome Game’s Heroine (LN) - Chapter Volume 2 1: The Magician’s Surly Disciple

An ordinary person who has never been in contact with games travels to the world of elves. Without a prominent background, no golden fingers, and no mysterious grandfather, where should he go?

This article is very cold-blooded and the protagonist is very selfish. If you think it is poisonous weed, don’t click on it. Thank you.

- Description from novelbuddy

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.

A good-for-nothing man married a beautiful girl but was kicked off the bed on the wedding night. Furiously, he wrote a bill of divorce and ran away.
He was schemed a car accident in which he nearly lost his life. However, it turned out to be a blessing. He swallowed the soul that passed through the outer world, thus obtained superb medical skills and martial arts.
Later on, with the silver needles and invincible martial arts, he embarked on the road of counterattacks and was committed to his great dreams.

- Description from Novelupdates

After finding an injured imperial big shot in a cornfield, Qiao Jing took him home and performed full-body surgery on him.When he woke up, he searched all over the world for the daring woman who had done something audacious to him. He searched the entire Imperial Capital, only to find out that the person was actually his wife from the countryside. Not knowing the truth, General Zhan was disgusted. “After 100 days, we're getting a divorce!”The medical expert said, “Master, there are still 90 days left until the divorce. I know a prince from the empire who has always wanted to meet you.”The agricultural expert said, “There are still 60 days left. The position of my granddaughter-in-law has been vacant.”The famous actor said, “Just one day left. The engagement ring is ready.”General Zhan couldn't bear it anymore and jumped out, pulling Qiao Jing in his arms. “You performed full-body surgery on me, and you still want a divorce?”Qiao Jing replied, “We agreed on getting a divorce in 100 days. Aren't you a responsible man who'll keep his word?”General Zhan said, “I am, but... I just want to be responsible for you...”Nine months later, the onlookers thought they had divorced. But to everyone's surprise, General Zhan appeared with Qiao Jing, who was pregnant with triplets, leaving everyone stunned!