This is the part of Katy Perry we never thought we'd see!

Over the weekend, Katy moved into an apartment with 42 cameras, live-streaming her life to millions of fans. The stunt was done to promote her new album Witness, but during the video, called Witness World Wide, fans witnessed something they never expected: KP's bare bottom flashing across the screen!

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While getting a massage, a naked Katy was situated underneath a towel, but when she moved on the table, her bare booty was momentarily exposed to the cameras. For many observant viewers, the flash didn't go unnoticed…

katy perry live stream butt

It's happened before, of course. Back in 2012, Katy suffered an unfortunate wardrobe malfunction while going down a slide at a water park. Her bare backside was completely exposed when her bathing suit bottoms fell off.

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KP, who recently broke up with Orlando Bloom, has yet to comment on the brief internet faux pas, but she did find time to mention her ex — actually three of her exes — while on screen. During a game with The Late Late Show host James Corden, a red-faced Katy proceeded to rank her past lovers by how good they were in bed: Diplo last, then her most recent ex Orlando, then, at the number one spot, her on-again, off-again beau of three years, John Mayer.

Corden wasn't the only one to make a guest appearance. During the live-stream, a slew of famous faces popped up, including Gordon Ramsay, Liza Koshy, Caitlyn Jenner, RuPaul, Kacey Musgraves, and more.