I thought spray on at first, too. However, closer examination shows that there are "bunches" around the calves. So then I thought that maybe she was wearing stockings of some sort and the rest was spray. Though, if you look at the top of her @$$ crack you can see the stretch of the fabric. My conclusion is that they're either extremely tight paints or she's wearing a thong with stockings and is sprayed. Overall, I'm leaning to extremely tight pants. I can't seem to distinguish a stocking cut off line and the "bunches" continue all the way up to the bottom of her cheeks.
Like I needed an excuse to study the pic even harder.