The Dawn of the Witch.

Saybil can't remember his life before he joined the magic academy. He has the lowest grades, because his amnesia leaves him unmotivated. One day, the school headmaster, Albus, orders him to participate in a dangerous special training. "I want you to spread the use of magic in an area where they hold witch hunts." This story is a spin-off of 'Grimoire of Zero.'