Katy Perry Lets Out A 'Love Giggle' On John Mayer Duet

Perry opens up about 'Who You Love' and what albums she's looking forward to most this year.

When it rains, it pours. And on Monday, the Katy Cats were not only gifted with the official release of Katy Perry's new single, "Roar," but also her duet with John Mayer, "Who You Love."

That same day, it was also announced that Perry will perform "Roar" for the first time ever during the 2013 MTV Video Music Awards later this month.

And the Paradise Valley cut is true to Mayer's musical form. It's folky and acoustic as the two real-life lovers trade lines about the one they love. "My girl, she ain't the one that I saw coming / Sometimes I don't know which way to go / And I tried to run before but I'm not running anymore," he sings.

Perry answers, "My boy he ain't the one that I saw coming / And some have said his heart's too hard to hold / And it takes a little time / But you should see him when he shines."

The two singers have been dating on and off since last summer. While Mayer confirmed their breakup back in April, Perry told Vogue in June that she still had feelings for her ex. Then in July, Mayer hinted at a reunion during a concert.

Perry opened up about the song to SiriusXM Hits 1, explaining the origin of her giggle at the end of the track. "I think that's just a love giggle," Perry explained. "It's like the ones that Mariah Carey had in 1990 and stuff like that . . . Yeah I think I was going for that, I think I was just so happy, I love that song."

Mayer's Paradise Valley drops August 20, while Perry will drop Prism on October 22. And despite previously denying that Mayer will appear on it, she told 95.5 PLJ's "The Ralphie Show" that he actually will make an appearance on the album.

"He played guitar actually, on a couple songs, which was awesome," Perry said. "He's just been a great support and that's all you can ask. If your partner is a great support, that's perfect."

In addition to her own new music, she also expressed her excitement for other new albums, including Lady Gaga's ARTPOP, which drops on November 11. (This weekend, Gaga's "Applause" and Perry's "Roar" were both leaked.)

"I think it's a really exciting time in music," she said." I'm excited to see what [Gaga's] record sounds like. I'm excited for a lot of people coming in the fourth quarter. I'm excited for the Beyoncè record when it comes. I'm excited for all of that. I'm such a fan of music."

Both Gaga and Perry will bring the a-POP-calypse to Brooklyn when they both take the stage at the 2013 MTV Video Music Awards, going live from Barclays Center on August 25. And while Perry will make the room "Roar," Gaga is also slated to perform new music at the show, bringing her "Applause" to the venue.