I had a guy once who was a real nightmare to deal with for the best part of his booked time, really difficult to communicate with and frankly quite rough as well. When eventually and much to my relief I managed to make him come, he asked if he could give me a hug, I let him. He then started crying, whilst "spooning" me, and said something along the lines of "this is what I really miss, I'm so lonely". I obviously did not expect that, and almost started crying myself, which is very unusual for me! It all lasted perhaps a couple of minutes, he then apologised, thanked me for a lovely time, got dressed and left.
On a couple of occasions I have seen punters come close to crying when they talked about their deceased relatives/children/wives, but they always composed themselves promptly and switched their attention to other activities...