Demi Lovato's back in London... and she's looking extra-sassy just the way we like her! This image appears in the gallery:This Week's MUST-SEE Pictures From The World Of Music 24. Demi Lovato's back in London... and she's looking extra-sassy just the way we like her! Picture: Getty 86 images See the full gallery: This Week's MUST-SEE Pictures From The World Of Music