Dobby

The other house elves had told him that there was a special mirror in the come and go room. It was whispered by the elves that the Headmaster had moved it there himself after the Boy-Who-Lived's first year at Hogwarts. Dobby sighed happily; he could never express enough gratitude to the Great Harry Potter for freeing him.

Dobby found the mirror and could make out the word 'Erised' on it and he looked into the mirror eagerly and then his ears drooped in disappointment

There was nothing special about the mirror at all! All Dobby could see was himself reflected just as he was (Dobby primped slightly in a small moment of vanity as he saw once again the reflection of his bright white uniform).

Dobby shook his head and popped back to the kitchens to earn his pay

A giant smile on his face at the thought