Harry: You really like cats. Like almost as much as Umbridge *shudders*; you adore the creatures and lots of your fellow students bully you for it, but Harry thinks it's cute, and he's always the first to step in, and defend you.
Ron: You talk to the paintings. Sure, it's not that weird, but you love to sit and have a conversation with a few, periodically. Ron sometimes likes to watch you chatting it up with Helga Hufflepuff.
Draco: You press your lips together kind of like when you're putting Chapstick on. You do this all the time which makes it hard for Draco to determine what you're feeling.
Fred: You bounce your leg up and down really fast. You rarely notice it, but do know it only happens when you're nervous. He likes to place his hand on your thigh to calm you down.
George: You practice spells. George likes this because you do it almost involuntary, showing you have a natural knack for spells. He sometimes joins in.
Neville: You play with the hem of your clothes. Neville likes when you do this because he knows you're really deep in thought. He likes to know you're thinking, because it prides him to say you're very smart.
Oliver: You don't like the fact you bite your bottom lip, but Oliver simply adores it. He knows whenever you do, you're either thinking really hard or really nervous. He takes this as a sign to comfort you.