I have 2 cats but my boy cat Twinkie, always paws and seems like he is really humping the sheepskin rug. He is already neutered and also, he kind of meows at my other cat if she crosses the path while he is doing what he is doing. He paws it and sniffs and looks like he is really humping it. When he is done, he never touches this rug, he will hop over it and so does Sugar. Does anyone know why he would be doing this?