Justin Bieber: I carry myself as a man now

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From the moment Justin Bieber released his recent single, "Boyfriend," in March, there was talk about how mature the 18-year-old sounded. Compared to his previous songs like "Baby" and "Never Say Never," for example, the song is a much slower, sexier jam featuring a deeper Bieber voice. Now the Biebs reveals to Rolling Stone that he feels much more grown-up over the last couple of years — and not just when it comes to his music. "I feel like I carry myself in a more manly way," Bieber says in his second cover story for the magazine, which hits newsstands Friday. "I don't carry myself as a boy."

For a closer look at Bieber's more manly moves, check out the super-cool mashup that YouTube user Raheemdaplayer04 created with "Boyfriend" and the very similar 2002 *NSYNC song "Girlfriend." How awesome is that?!

Someone who's definitely noticed that Bieber's not a little boy anymore is his girlfriend, actress and singer Selena Gomez. The "Love Me Like a Love Song" songstress, who turns 20 on July 22, has been dating her guy since late 2010. While there's been some speculation that Bieber could lose some of his young fans, known as Beliebers, because of the relationship, his manager Scooter Braun disagrees. "Personally, I think that's all a bunch of bulls—t," Braun tells Rolling Stone. "Yes, there's gonna be some girls that if they see him with a girlfriend, it kills the dream — but there's also gonna be girls that see him with a girlfriend, hear about the romantic things he does and want him even more." Bieber probably really scored some points with those fans last fall when he rented out L.A.'s Staples Center so he and Selena could have a private dinner and a screening of the ultimate date flick, "Titanic"!

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