If you were in the desert, and there is nothing but miles and miles of sand. no clothes but you have a dog with you. and you have to take a nasty greasy shit, but you have no shit tickets (TP). would you let you dog lick your asshole clean?
Well, i would indeed let the dog lick my asshole because that will fill the dog at least and my ass would indeed be clean. This would in turn make every thing easy for my stay in the desert.