After Katy Perry's future husband Russell Brand allegedly got handsy with a paparazzo recently, the singer still managed to smile this weekend -- close pal Rihanna threw her a Las Vegas bachelorette weekend.

"Signing up for a liver transplant now," Perry tweeted on Saturday, poolside at the Hard Rock Hotel beach club.Perry, Rihanna and 25 other guests luxuriated in a private cabana, fully stocked in libations including beer, Champagne and vodka, says People magazine.

Also on deck? "Inflatable objects consistent with bachelorette parties."

Totally expected, given Perry is the same pop nymph who brought us the exploding-whipped-cream-can brassiere. Perry also donned a prop bridal veil, clipped to the backside of her bikini bottom.