Rihanna recently posted an Instagram picture which featured her bare behind in a pair of shorts that looked more like underwear.
She was on the set for her new music video, and this photo might be a picture from it.
But it also could have been aimed at ex Chris Brown, who is now dating Karrueche Tran again.
It is more likely, though, that the photo is from her new music video for Pour it Up. In the song, she sings about strip clubs and strippers, so she might be acting as one in the video.