"And don't come out until you're properly dressed, young miss!"

Seems like the apparition is somewhat confused, you're not a girl, are you? A quick glance downward reveals yourself still unchanged, though with the nature of this house, it wouldn't be all that surprising to have found yourself transformed. Looking around the dim closet, there are all sorts of clothing, from girl's dresses to a boy's suit - the closet may have been used for storage as people grew out of their clothing - from the little you saw of the bedroom, it doesn't look like it had been used for quite some time before even the house became known for being haunted.

So ... the poltergeist expects you to wear something from here?

Instinctively, you reach for the suit, and then pause a moment, before taking it off the hanger. It did call you a 'young miss,' perhaps it would take it amiss if you came out of the closet in anything other than girl's clothes. It did, after all, command 'properly dressed,' didn't it...?