It's a girl. Dark hair, sharp cheekbones, an amused glint in her eyes. She's wearing Slytherin robes, but the tie is undone, hanging loose around her neck.

She gestures inside with a jerk of her head. Inside, you can see two other girls. One with dark skin and a sleek bob, reading a magazine. Another with a cascade of blonde curls, fiddling with a silver bracelet.