Genius Mage: I Live in the Girls' Dorm Thanks to My Return System

With a rune stone that grants incredible rewards for every gift he gives, Will goes from a nobody to a magical prodigy. He ends up living in Grand Academy's girls' dorm, puts arrogant nobles in their place, and defeats abyssal monsters. But when the academy's own headmaster turns out to be the mastermind, can Will play his last card and save everyone?