Demi Lovato isn't the squeaky-clean Disney Channel star she once was.

The 19-year-old "Give Your Heart a Break" singer recently posed for photographer Tyler Shields, who shot a series of racy images featuring Lovato seductively sucking a lollipop and smashing a mirror.

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"We wanted to show that Demi is all grown up from her Disney days and is a really beautiful and powerful woman now," Shields tells Us Weekly. "When I showed her the images she was really excited and could not wait for us to post them so that her fans could see a different side to her."

Lovato -- who will perform at the Iquique Festival in Chile Saturday -- was so impressed with the shots that she's now using one as her Twitter avatar.

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"When you meet Demi she can be a real force of nature, and this particular image of her smashing the glass really captures that," Shields explains. "She looks amazing and was really great to work with."

Tell Us: Are you surprised to see a more adult side of Demi Lovato?

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