Katy Perry’s new single, “Waking Up In Vegas,” had some real-life inspiration.

In a new chat with PopEater.com, the larger than life vocalist reveals that she and an ex-boyfriend staged a Sin City wedding ceremony when she was 21.

“We decided to get fake married,” Katy, now 24, explains. “I was 21. We took all the pictures with the minister, with the fake cake, in the fake chapel and got a fake marriage certificate. We went and bought a wedding dress and a suit at a thrift store, and scanned the pictures and the certificate to my family members, my manager at the time [and] totally freaked the s— out of them.”

“It was the most hilarious, stupid prank I’ve ever pulled,” she laughs. “I still have the wedding dress and the certificate.”

Of her latest release, Katy explains: “[It’s] basically a song about getting into trouble with your best friend or your boyfriend or your girlfriend – or whoever you’re with – and not having any ‘I’m sorry for what I did.’”