I have always been fascinated with female masturbation.
When in college, I had my share of girlfriends. One night when playing a game of 'I never,' one girl said, 'I never masturbate.' Anyone in the group who had masturbated had to admit it. Others had previously admitted to all kinds of activities, but only one girl and I admitted to masturbating.
Later in that school year, one of the girls who had denied masturbating told me that she actually masturbates all the time. I became immediately aroused. I told her that my fantasy has always been face-to-face masturbation. We had fooled around with each other many times before. That night, we went to her room which was an upstairs/downstairs type room and stripped off our clothes. She began fingering herself while I pulled on my cock. We both came really hard.
Later that week, her roommate, who had the upstairs bedroom, told me that she heard the whole thing. I assumed and fantasised that she masturbated right along with us.