This little scene broke my heart. The girl who believed in nargles, in wrackspurts and blibbering humdingers, has become the girl who believed no more.
See, the thing that nobody understands, is that Luna believed in things that had proof. She’s a Ravenclaw, a genius, an expert in the unseen but proven. I mean, if she’d started talking about Thestrals before Harry had been able to see them, saying that there was an invisible winged horse pulling the carriages that only people that had witnessed death could see? You’d have thought THAT was crazy, too.
Luna knows Nargles and Wrackspurts are out there. As far as she knows, there’s proof of it.
But seashells hanging in a door? Those don’t do anything, nothing but give you a false sense of security.
It’s not that Luna doesn’t believe. It’s that now, as always, she’s frank and straightforward. Seashells can’t keep the evil at bay. Nothing can.
Thank you. She is not a naive little kid who believes everything you tell her. She just knows some things we don’t. Because she looks harder.