When the Rat Queen bites the Rat King's ear as a punishment for being whiny, he stumbles away from her, pressing a hand to his ear and crying "You bit me!", looking very pained. However, when the Rat Queen stops yelling at him, you can still see him standing in the same position and with the same pained expression, but in the next shot (a second later), he's standing in a quite normal position, looking angry rather than pained.