Someone lifted her skirt, made it look like a jack-o'-lantern, then chained her wrists and cuffed her panties. Not too hard to comprehend.
She could almost certainly wriggle her arms and dress free, but I bet the undies are a loss.
Well I got that part, it's more that it's such an elaborate prank. And with that long skirt I think she can survive with some torn panties until she gets home if she were to get free.