The Heavenly Demon of Terror - Chapter 255: The King of Beasts Vs The King without a Crown.

[Are you crippled?][Did your fiancé break the engagement?][Did you lose your family to a demon attack? Are you the last surviving member of your clan, seeking revenge?][Does your family look at you with pity because you're the only one without any innate spiritual roots?][Are you tired of being told that you're a 'waste of resources'?][Are you stuck with no way to progress? Are you tired of being weak and helpless?][Well, have no fear! This Supreme Master is here to help you!]

When I cleared the final chapter of a game that was a national failure, I became an unnamed side character in it.

A non-standard, unmeasurable, EX rank supporting character.

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.