Justin Bieber is good at many things: singing, dancing, making teenage girls bare their claws. Rapping, however, is not one of them. Though the Biebs pals around with industry heavyweights like Drake and Ludacris, when he moonlights as his rap alter ego Shawty Mane, his nasally, air-sucking delivery leaves a lot to be desired — no matter how fast he enunciates. "I'm just a pop singer," he admits following an awkward and preplanned freestyle on English DJ Tim Westwood's make-or-break hip-hop show. You have to hand it to the kid, though: At least he has guts.