That was cute. And Luna was in character, (so was Ron ...) which is impressive to me atleast because I've seen several authors attempt and fail at portraying her. No less actually getting in her head. Good, I liked it.
Creepy. Good. Angsty. But creepy is staying in the front of my mind. That was definitely a neat and different idea, in particularly for a one-shot, and you pulled it off very well.