Fortunate Slave Oily Ass Worship

My slave has been a very good boy today, so Ive determined to give him a bit of a treat. Well, he thinks its a treat - its more of a demonstration of just how much power I have over him! He can have the thing he most desires right in front of his face and still not love it the way he would like to! I am going to oil up my butt and shove it in his face - will he overstep the line? Or will the power of my posterior mesmerise him entirely?