Katy Perry singer performance st. patrick's day wig stage boobs Katy Perry singer performance st. patrick's day wig stage boobs Mr. Paparazzi

Katy Perry let it all hang out last night in London on the first night of her California Dreams tour.

Wearing a series of sparkly, sexy costumes that left little to the imagination, Perry rocked the Hammersmith Apollo, performing to a sold-out crowd.

Perry recently complained about the strict diet she was on in order to look that good wearing that little:

"I'm on a meal plan, which absolutely sucks," she revealed in a recent interview. "But on Sundays I get to have a cheat day where I go buck wild and eat In-N-Out Burger."

Whether it sucks or not, all that discipline has clearly paid off!

Click through the gallery to see more of Katy's wild wardrobe!