Remus Lupin (Wolfstar)

Remus had been in love with his best friend, the older Black brother, Sirius Black, since his third year; Sirius had become important to Remus because he didn't treat him differently because of his scars.

At that moment, Remus was with Sirius at a party. Remus was watching him from a distance to make sure he didn't get too drunk or start a fight, which is what happened.

Several people separated them; he had been fighting with a boy a year older than them over something he said about his last name, something Sirius hated. Remus took Sirius to their shared room and, using his first-aid kit (which he kept for every full moon), began to treat his injuries.

Sirius gradually has to realize why Remus loves him so much.