30 years ago I was single and in a relationship with a married woman. We met as often as we could for sex and sex play.
One day she was in my parent's house with me, making coffee. Waiting for the kettle to boil, she unzipped me as I fingered her pussy. This continued until she stopped to pour the water into two mugs then she stroked me to the point of orgasm. As I came, my spunk shot out onto the worktop and some landed in both mugs. We both laughed but decided to drink the coffee anyway!
There were many occasions when she masturbated me, some in public (eg the swimming pool).
Ah memories, and yes, it really did happen.