Harry knew he shouldn't be out wandering the castle after curfew, especially not after the mess with smuggling Norbert out of the castle. Gryffindor still hadn't fully forgiven him and his friends for the point loss. Still, on a sleepless night, he couldn't help the temptation to get the invisibility cloak out of his trunk.

He was in a magic school after all, and so many parts of it were unused. So many things were hidden away. He couldn't help but wonder what else was waiting to be discovered. He had found the Mirror of Erised this way, a painting of a viking who enjoyed regaling him with stories late at night, alone in a hallway because he said he talked too much, a little nook that was like a small version of the library, even a room he would swear as decorated for a party in the 1920s.

At night, Hogwarts was his.

The room he found tonight had been long abandoned. There was dust lying white on the desk in the center of the room, on the floor, everywhere but one spot. There was a silver frame, like the Mirror of Erised, holding something he might call a mirror if the glass wasn't green. He approached it cautiously, mindful of the warning Professor Dumbledore had given him about the Mirror of Erised.

Staring in the mirror, however, did not produce images of his family, the generations of Potters before him. No, instead, peering into the emerald mirror, he saw himself in green pyjamas. He looked down at his own grey hand-me-down pyjamas and then looked back up, only to be watching himself in school robes, taking tea with the Astronomy professor.

That was odd enough, he took a step closer and noticed the trim on the robes the Harry in the mirror wore. Harry swallowed hard, remembering his Sorting and begging the Hat not to put him into Slytherin. He sat down, with a kind of macabre curiosity and watched.

The idea of the arguments with his best friend turned his stomach. Was there evil in him? Did Slytherin just make people the worst versions of themselves? Why else would Ron turn on him, Ron who had been his first friend, when they had shared candy on the train.

But then...there was Hermione, decked out in silver and Green, arm slung around his shoulders as they bent over books, studying, a pretty blonde girl he vaguely recognised across from them. Guiltily, he remembered all those times he had been distione had asked him to revise with her...but didn't Slytherin hate muggleborns?

He pulled himself away from the images when he saw himself jogging around the pitch with Malfoy, his stomach rolling. What did it all mean? What was this mirror? Slytherin had never been his heart's desire. Malfoy was a bigot and a bully, a skinny, blond Dudley.

The Mirror of Erised showed your heart's desire.

The Green Glass showed his fears.