I had one very special experience. I met a masseur. His rates was at the very low end, though he said I would have a happy ending, I didn't expect more.
When he almost finished my back, he focused on my butt, and began to rim me. I got excited, and moaned. I guess he got the signal, so he crawled on the table and fucked me.
After I turned over, he also put a condom on my cock and rode on me till I came.
That was a pleasant surprise, I don't know If he did so with all clients, but I couldn't contact him any more when I wanted to go to him again. His ad also disappeared.