John Mayer and Katy Perry's 'Who You Love' Hits Web (Audio)

Hear the real-life lovers perform a ballad from Mayer's upcoming "Paradise Valley" album.
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Katy Perry and John Mayer

"Roar" isn't Katy Perry's only new song.

The singer is featured on on-again boyfriend John Mayer's "Who You Love," a track from his upcoming Paradise Valley album. The set is due Aug. 20, but the duet has made its way online.

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The soft ballad, punctuated by Mayer's lead guitar licks, finds the pair trading verses and sharing the track's titular chorus: "Love who you love, who you love."

"You're the one I love," Perry sings to close the track before bursting into a giggle.

Perry's own Prism is due Oct. 22. "Roar," the lead single, is out now.