Katya holds on as long as she can. The boot in the face is annoying, sure, but she can hold on a little longer, shaking her head back and forth to try to work it out of his grip. Werewolves, when they're full grown, are roughly the size of a pony. He's not exactly dealing with a poodle here. Her snout hurts but her father told her to suck up any pain until the very end.