I've seen that many times. I believe he,s claiming her. lol (although, it does seem disrespectful).
If it helps, I had an 'interesting' experience just yesterday with my toy poodle. I took him to Petsmart to look for Halloween bows for his hair and, as per our habit, let him empty himself before going in. He snuffled around a bit, marked a few things and then saw another dog and walked over to me and hiked at me. Thankfully, I was watching him closely and jumped back in time! I guess Bug isn't going to share me with another dog. I suppose I should be flattered? :/
Good thing he's cute and loves my chi!