As another reviewer posted, the actual material used for this dress is very thin and matte, not shiny.  I will most likely white leggings and a tight white t-shirt underneath.  I'm 5'4" and 115 pounds, and got the size small.  It fit well, just the zipper part stuck out a bit in the back.  An XS probably would have been unflattering.

The belt is ridiculously huge.....falls right off, so I'll have to get some velcro to make it smaller.  It's also not white like in the picture, more of a cream color.  The wig is also tiny....fits my 6-year-old great!  But looks silly on my head.