Private Tutor to the Duke's Daughter 0: Tales from the Royal Academy

A lowborn boy with a gift for magic sets out to defy precedent and win a place in the prestigious Royal Academy. Its infamously challenging entrance exam forces him to team up with the daughter of one of the kingdom’s most powerful nobles in a meeting that will change both their lives forever. The aristocratic old guard scorns Allen for his humble origins, no matter how many times he proves himself as a sorcerer, and calls Lydia “cursed” because she can barely cast a spell, no matter how often she shows her skill with a sword. But as long as they support each other, they can be more than a match for anything the academy throws at them. Joined by a misfit princess and an enigmatic student from abroad, the pair take their first steps toward proving the world wrong. Meanwhile, whispers of a potent drug and a dragon-worshipping cult have the kingdom’s leaders on edge.

Source: J-Novel Club