This one is a very special celebrity selfie fail. You may not be able to tell from the cropping of the photo, but that's Modern Family's Sofia Vergara. She's getting some kind of treatment on her rump, though I'm not sure what it could be. I could guess, but I know that I'd be wrong. I know that because I'd guess things like Bootylicious Treatment or Rump Roasting. Neither of those things exist.
Whatever is happening to her lower, rear extremity, Marilyn Monroe is conveniently placed in the background to look like she's laughing at the Hollywood star. It's as if Marilyn Monroe is saying, "I used to have to do that too. I know how it is, girl." Either that or she's feeling relieved that she didn't have to do those kinds of procedures back when she was a star.