Most of my experience with surprises during sessions have been rather subtle (and some of them have been negative). However there is one that I have been think about a fair bit of late even though it occurred long ago (at least 12 years)

There was a session at a dungeon. The manager asked if it was OK if a domme who was being was included (no extra cost). I said sure. It was a very intense CP session. Essentially I told the Domme to make an all out effort to make me cry. I was foregoing a safeword. She was sure she could succeed using a cane.

Early in the session I could hear her say some informative things to the trainee who barely said a word. When the caning got underway I was blindfolded. After that I only heard a little bit of training talk. However after a while I began to hear a different woman's voice talking in my ear as she used her body to help immobilize my body for the worst of the caning. While she was doing this she frequently grabbed my genitals. The way she did it was not in a pleasure giving way (to me) but neither was it true CBT but rather as if she enjoyed grabbing guys there in an assertive manner.

I was increasingly suspicious that it wasn't the trainee I was hearing. And when it was all over and the blindfold was removed there were two women in the room but neither of them was the trainee. The second woman was in street clothes! I didn't know what to make of this. I thought the dungeon might be trying to charge me for a double Domme session I had not requested. But no there was no attempt to charge me for the second lady. A cane had broke during session and I offered to pay for a fair price for that.

I asked the mystery a few questions and found out she was an independent. At the time I was very tempted to ask if she had a business card but didn't (thinking back I am not sure why. I guess I was worried the main Domme might feel slighted if I did. I can be silly that way sometimes).

Oh and I did NOT cry. I did do some begging of the mostly real kind though. I was a bloody mess and my butt took a very long time healing. After this session I decided that I had better accept that pain alone would not make me cry. I also decided that heavy bleeding should be a hard limit.