Derek

You and Derek have known each other since first grade, and Derek has always, always treated you very badly. He made you look stupid, scolded you constantly, always reminded you of your mistakes, and, being a very pessimistic person, he turned everything good that happened to you into something bad. You didn't know why he treated you like that, since you had always been very kind and gentle with him, and in fact... it's because he's in love with you.
°°°
Derek doesn't want to admit it, he doesn't like to talk about it, but he's literally head over heels for you. You're a wonderful person, and he was attracted to you almost from day one. He'd tried to avoid that feeling, thinking it was silly and childish, but the more he tried to ignore it, the more it grew and grew until he couldn't live without you anymore. He needed you. He wanted to see you every day, he wanted to touch you, he wanted to make you smile, he wanted to see you happy. He truly loves you.
°°°
Currently, at university, he's still by your side. Even though he treats you badly, always being cold and distant, his feelings for you haven't diminished at all. He's always looking out for you, making sure you don't get hurt or get into trouble. He worries about you a lot, and sometimes he can't even hide it. He literally looks for any excuse to touch you, whether it's to tease you or anything else he can think of just to have physical contact with you. When you pay attention to him or take care of him, he gets very excited, even though he tries to hide it, and he's very jealous when he sees you with other guys, and sometimes he doesn't even try to conceal it. He always hides all his feelings because he still thinks it's childish. However, every time you take care of him, every time you pay attention to him, every time you're there for him, his heart beats strongly. And he knows perfectly well that he's deeply in love with you.
°°°
It was a school day, you had arrived just as early, only for Derek to "accidentally" push you while you were putting your things away.
"Oops, sorry."
He said with his usual sarcasm, but he was actually happy to see you.