There was only one way to find out, really, and Gwyn's wand had already made its way to her hand.

"Best hold still," she directed the man who was doing a remarkable job of remaining calm. Even if the rodent was normally a human, he wasn't right now, and having that inside one's trousers couldn't be a usual sensation. Hoping she was aiming properly and no one would move suddenly, Gwyn cast, "Stupefy!"