What does UTR stand for? When I look it up I get universal tennis rating. lol.

The relationship you describe is much like what I had with a long time personal slave. My husband was fine with it. They would even get together and watch football. It is an odd dynamic to be such close friends but have the Mistress/slave element to it. It came naturally for us. It sounds as if you have a rare find in a positive relationship that is somewhat similar. That is awesome.