Sorry, its my dog and I know whats she's doing - I know dominant behavior when I see it, and I know when someone is just set on getting "happy", and thats all she is doing. I know it makes people uncomfortable to think that animals might just be seeking pleasure, but thats been well documented...
I have a dog, and she is always mounting things... blankets, toys, women's legs,etc. Many people have insisted that she has "dominance" issues, but that's not it at all... she is enjoying the activity, and will do so compulsively when in the mood. Its actually pretty obvious what her objective...