First of all, I guess people missed the point that these are paparazzi photos and they were taken without her consent. You all act like you're seeing the final product. We don't know what direction they're going in or what will be photoshopped or airbrushed.
Secondly, she has on nude underwear. She's not naked.
Thirdly, her body is fine. Not every woman has to have this curvaceous body with a humongous ass to be considered sexy. The beauty standard is so ****ed up nowadays. It's the reason why over 80% of women are dissatisfied with their appearance, over 90% of women wish they were thinner, and why they run to the doctor to get plastic surgery. The pressures that society put on woman to look a certain way are gross and it's people like some of the ones in this thread that are part of the problem. We should be embracing the fact that they do come in all shapes and sizes instead of being fickle.
There's never nothing "unclassy" about a women being confident with her body and embracing her sexiness. It may not be according to your standards, but it's hypocritical how some of the same mother****ers who drool over nudes from guys on this site are calling Rihanna trash because of some photos that were taken against her consent.