I Attained Invincibility In The Real World - Chapter 53 - 52: Upgrade and Pile Technique Perfection

This is the tale of Arin, a once kind-hearted and gentle child, now a man hardened by the cruelty of society and the brutal trials of life—a man transformed into a ruthless criminal, devoid of mercy. As his world was collapsing, fate transported him to a new realm. This world, more vicious and savage than his own, was steeped in magic and dark mysteries.Ironically, it was in this fearsome world that Arin, now an undead being, began to rediscover his lost humanity. Through battles and bloodshed, amidst the clash of sorcery and steel, he started to reclaim the compassion he once hated. This is not just a story of survival but a saga of transformation. Follow Arin’s journey as he rises to power, determined to become the ruler of this harsh world. In a twist of fate, he now seeks to save the very humanity he once wanted to destroy.

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.

Mortimer Zhu is an extremely unfortunate high school student who accidentally enrolls into an academy of a dubious nature, where it is the norm to jump in front of moving trains, get dismembered during orientation, and crushed by vindictive bouncing classrooms. Can he stay alive or will he die from the rigors of school? Why have evil spirits suddenly acquired a taste for his flesh?

- Description from Novelupdates

Yo, Hi! I’m Frank, I made a deal with a demon to pay me some money for receiving a guest for a few days every week.
I had no idea about what I have done.
On May 1st, Conan ‘the God of Death’ came to my house. I was forced to let him in and we get involved in a criminal case.
On May 8th, Bruce Wayne ‘Batman’ came to me. I was forced to follow him to fight crime.
On May 16th, Hannibal Lecter, The Silence of the Lambs, came to my home. I can only say that I really can’t stand my guests.

- Description from Novelupdates