I Am the Nanny of the Villain - Chapter 114:

Song Yi found herself transmigrated into a novel, becoming the female protagonist of an old-school Mary Sue story.Gentle, kind, beautiful, and graceful, she was the unattainable ideal in everyone’s heart. The aloof top student fell from his pedestal for her sake, while the reclusive young man fought against his family for her.All of this sounded quite nice, but there was just one problem – this novel had a bad ending!!!

She fought in the Battle of Changping and witnessed the killing of hundreds of thousands. She once led the Qin Iron Calvary and battled against the Six Kingdoms. She has seen a third of the land and witnessed the breaking of mountains and rivers. The sound of a grand zither and the light of a great female emperor. A prosperous world that was forged on the battlefield. Yet, these two thousand years are forgotten from history.

- Description from Novelupdates

After dying in laboratory tests, Klaus transmigrated to a Sorcerer World, in a strange and peculiar character whose existence is an enigma. He knew this world, for it was the world of the novel one of his students wrote. He also knew the character because he created it. But it was a discarded character; it never appeared in the novel. How could he have transmigrated in it? Reality hit him soon after when he was sent to cross through the first test that every sorcerer must pass to awaken his abilities. There, he will have to fight against powerful monsters, which they call Curses, and against other Sorcerers, all to try to enter the select group of Sorcerers to discover the secrets that await in this world and understand his arrival to this and his existence. Just when he thought his journey might be boring, he received a peculiar and mighty power bordering divinity, capable of making him reach unimaginable heights. Although a bit dangerous...