Ariana Grande got festive with Jimmy Fallon! The songbird, who stole the show at the 2013 AMAs, performed her cover of 'Last Christmas' for 'Late Night.'

Grande hit every note perfectly and even dressed the part. She rocked a lace red A-line frock with a white jacket and accessories, looking totally cute. Accompanied by the Roots, you'll wonder why anyone would break her heart -- especially on a holiday! (Nathan Sykes, are you paying attention?!)