One of my favorite things in life is when a fit girl wears leggings. Nothing turns me on more. However, the cardinal rule is to either wear a thong or go commando underneath. Well, someone forgot to tell Katy Perry about this because it looks like she’s sporting some granny panties, or possibly Spanks to hold all that post John Mayer break-up weight. Anyway, hopefully other girls can learn from Katy’s fashion faux pas and avoid having an embarrassing moment.