The Magician Who Rose From Failure: Volume 6 by Hitsuji Gamei

Now thirteen years old, Arcus crushes the entrance exam for the Royal Institute of Magic, and he soon begins his new life as a student. Disowned for his supposed lack of ability, he makes waves both good and bad when he quickly outstrips his distinguished peers, rising to the top of his class. His success does not escape the notice of Claudia Saifice, granddaughter of the Institute’s headmaster. What exactly does she have in store for him?