The Little Mix girls show us exactly what Hogwarts would be like if it was an American high school, as their nerdy counterparts get sassy with the help of some 'Black Magic'. The promo shows off ...

Since then, she's become Little Mix's go-to songwriter, composing hits like Black Magic and the Brit award-winning Shout Out To My Ex. "Camille knows us so well," says the band's Perrie Edwards.