It's Luna! Luna is, and always has been, the main host of Practical Lunacy. She is, quite simply, The Queen of Lunacy! She won't miss the chance to let you know that it is "HER SHOW!"
She's also a Whovian, in case you can't tell by the dress! And she likes to goof off, because, just because you're a grown-up, doesn't mean you can't still be childish sometimes.