The "Roar" singer asked her fellow pop stars for the bizarre gifts when they shared a dressing room, and they were apparently happy to oblige.
After performing at the online broadcaster iHeartRadio's listening party to launch her new album "Prism" on Tuesday, Perry took questions from fans and was asked what she keeps in her purse.
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She replied, "One of the first times I went to the Grammys, I got to share a dressing room with Miley Cyrus and Taylor Swift and I asked them for a lock of their hair from each of them, which is totally creepy, but awesome. I put little bows on them individually and put them in my purse. And that was my little secret and I'm a freak!"
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