Is it possible for dogs to have a thing for canine S&M? It seems like one of my chihuahua's favorite thing to do is get dominated, scratched, and bitten by the other chihuahua. And she bites really hard, to the point where he starts sobbing in pain, but he just keeps going back for more. When he was at the pound, his sister did the same thing and when we separated them, he through the gutter into the next kennel to get back to her. He has other dogs to play with who want to play with him, but they don't hurt him like this dog does. I guess there's nothing wrong with it if that's what gets him off, but it's still kinda creepy.