A concert is a party, but some people always party a little harder than others. Like this Brazilian fan at Katy Perry's Rock in Rio gig, who was apparently not that preoccupied with pop star personal space. Perry brought the ebullient young woman — in a smiley-face halter top — up on stage for a little quality time but ended up getting more than she bargained for as the young woman proceeded to kiss, pet and grope Perry at any given opportunity. "I think she's rolling," the singer surmised. I mean, probably?'

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