This Halloween costume isn't quite what meets the eye

This Halloween costume can be summarised in one sentence: Business in the front, party in the back.

For the purpose of the video, the filmer can be seen knocking on the door and asking for candy from her brother, Nicholas Smith. He obliges and turns around to get some, revealing the back of his t-shirt and pants are cut off to show that he is wearing a bra, ladies' underwear and translucent tights.