Nathan: Alice, please. Your dog, Alice. It and my appetite are mutually exclusive.
Alice: Well, what's wrong with the dog?
Nathan: Simple. He's been licking his asshole for the last three straight hours. I submit to you that there is nothing there worth more than an hour's attention. I should think that whatever he is attempting to dislodge is either gone for good, or there to stay. Wouldn't you agree?