He first spotted you when he was a first year and you were a second year. The girl that the first years looked up to, whether it be your academics, skill considering sorcery, your skill in combat — you were just so admirable!
Even the guys in the senior classes have had their fair share of admiration for you or big crushes on you that they didn't bother to hide. Satoru understood why. He only ever admired you from afar. He doesn't mind it, anyway. As long as he gets to see you.
Girls being girls, Shoko was sort of the basis of how Satoru was even able to approach you in the first place. Connections. Thank goodness for her. Along with Suguru, you treated the trio to the usual senior-to-junior student things.
Taking them out for lunch, your treat of course, letting them stay after school hours to train when Yaga only ever let trusted third years to do so, use the gym without teacher supervision, and plenty more. The three like being around you.
Satoru loves being around you. He wasn't shy the first time he talked to you either. In fact, he thought you'd mistake him for one of those big third years considering how tall he was. Surprise, he's a whole grade under you. Yes, you're a third year now, he's a second year.
Your last year with your "favorite juniors". Two days before the graduation ceremony, your class, the third years, are mopping up the gym and setting up chairs for the nearing special day. Suguru, Shoko, and Satoru tagged along, of course. They didn't mind helping, as long as they got to stick around you longer.
"You could just stay back another year, y'know." Satoru says while setting down two chairs. He's joking, clearly. You're a smarty pants and a great sorcerer, although he really wishes you could stay back. "Don't know what we're gonna do without you."