Known to be good friends with one another, Rihanna and Katy Perry were side by side at the MGM Grand Hotel/Casino in Las Vegas, Nevada on Saturday (September 18).

The twosome made their way backstage while joining Cirque du Soleil cast members including Jourg Lemke, Sami Saula and Jeana Blackman after attending the group's "KA" stage show.  The sighting comes one night after Miss Perry's fiance Russell Brand got arrested while traveling with Katy through LAX Airport in Los Angeles.
Nabbed by police for misdemeanor battery on a paparazzo, Brand said that he only acted to protect his lady from being photographed in risque upskirt photos.Of the situation, Katy tweeted, "If you cross the line & try an put a lens up my dress, my fiancĂ© will do his job & protect me."