Fallen Mage Regressor
F5/100Web serial by Lemonoid
Death makes exceptions for all the wrong people. Malfrasius wasn't trying to destroy the world — even as everyone called him a Dark Lord, he fought to save them. The Heroine didn't believe him, and his life ended with a blade between his ribs. When he woke up six years in the past on his way to magic school, he resolved to do things the right way and without attracting attention. But the butterfly effect has a funny sense of humor. His clumsy changes to the timeline have landed him in a team with two members of the Heroine's party, the academy's top prodigy suspects he is her equal despite his F-grade core, and his loyal maid is growing suspicious of his sudden personality shift. Malfrasius wasn't trying to destroy the world. It's just a shame the world seems so intent on destroying him.