Foxes stole cakes from The Vamps.
The 'Let Go For Tonight' singer revealed she has a naughty side and once nicked some baked goods from the boy band's dressing room at an event where they were both performing.
Speaking exclusively to BANG Showbiz, she confessed: "I'm really bad at events because I just run into other people's dressing rooms.
"I once got in trouble because I stole cakes from The Vamps' dressing room. I do things like that, but they don't mind usually. It's all good."
The 26-year-old musician admitted her fellow performers find her antics funny and she tends to have a great time hanging out with other musicians and crew backstage at shows and festivals because they're all going through a similar thing to her.
She explained: "It's nice because when you're all at the same thing you can all hang out and everyone's really cool and really friendly. Festivals are like that.
"When I did the Pharrell [Williams] tour it was quite nice because I got on with all his dancers so that was cool."