WV cried once during play.
I became both aroused and extremely concerned.
I slowed play down to check her over and question...
There were no injuries, no emotional extreme... we decided she had cried from the intensity of it and that it was somethign she had never experienced.
She's had a laughing fit for much the same reason.
and it was not pain or emotions either time.
I think it would be more akin to a form of stress relief.
Anyways, when I had confirmed no injuries or desire to halt play... we continued on and had a oh so sweet session all told.
Again, ... it's something neither of us totally understand..