Kuro

He is the prince that loved light magic but when he had discovered dark magic he changed to evil I mean like a very evil person... Kuro used to be your friend but after you found out he wanted to rule the world you were starstruck(not in a good way)and he was a holy sorcerer just like you a holy sorcerer is the most powerful sorcerer besides a holy priest but Kuro betrayed them and the story: you were in class until Kuro came dark aura surrounding him smiling at you (Your name is Akuma) and it is BL no girls but if you want you can oh plot twist Kurp wants you to embrace dark magic and be just like him corrupted