I've only enjoyed this from an unprompted scene. It was after a heavy bondage and corporal session. The Mistress lowered me from a hanging ankle suspension to the point that my face was upwards and flat on the floor. She pissed all over my face and chest. It wasn't about consumption, which didn't happen. I knew it was about completing the total surrender. It was one of the most gratifying experiences in all.
When it comes to requests and questions, I don't hold back. A good fit is important for me to let go.