I Was Just a Cleaner... Until I Got the Demon Extraction System - Chapter 1: Cleaner Job

A story of Gin, a young man who lost his memories before the age of 17 and became a magician. Living a quiet life running a cafe while researching magic, he is suddenly thrust into an unknown world. Moving between Earth and a realm filled with danger and secrets, Gin must rely on his knowledge, skills, and magical prowess to navigate the perils that arise. Ruthless and determined, he will stop at nothing to uncover the truth behind his lost memories and the mysteries of the world, using every tool at his disposal to rise above all

Why do Gods of Transmigration love to murder their benefactors instead of asking for their help a normal way?That's how Karl got started as well. Murdered by a goddamn goddess, dumped into another world, and told to save her from her problems. You'd think gods would have their shit together, being gods and all. But apparently they do not.Karl, a teenager, who felt the inequality in his already struggling life more than ever before, finds himself transmigrated as a vice principal of a magical academy. The council accuses him of his incapability and his inexperience, believing he's not fit to lead them to the top.[ Mana meter unlocked: capacity F ]Even his cheat skill seems like a useless gimmick as Karl faces the worst students of the academy and the most difficult professors.That goddess better sends his paycheck to his parents in his old world because Karl isn't going to work for free, and if he does this job, the least she could do is pay off their debts.But then again...“I won't accept this fate handed out to me. This world might offer me the fantasies but they can't give me the warmth of my loved ones.”Would he be able to meet the Goddess and return back to his world or would he gets buried under the history of the lands that had once housed Gods and Demons alike?

The celestial celestial beings who lived for more than 100,000 years were born and reborn in a small monk in a human world.
His motto: “It’s not as good as a medicinal medicine for ten years of hard work.” “Even if you practice a copper-iron bone, it’s not enough for my soldier’s attack.”

- Description from Novelupdates

Chen Yan travels between worlds, ending up becoming an honorable prince in a medieval fantasy world. Yet this world was not quite as simple as he thought. Witches with magical powers abound, and fearsome wars between churches and kingdoms rage throughout the land.

Roland, a prince regarded as hopeless by his own father and assigned to the worst fief, spends his time developing a poor and backward town into a strong and modern city, while fighting against his siblings for the throne and absolute control over the kingdom. Join Roland as he befriends and allies with witches and, through fighting and even farming, pushes back invaders coming from the realm of evil.

- Description from Novelupdates