This was my first lap-dance experience. It occurred many years ago in an Illinois titty-bar, adjacent to the Missouri border.
As I recall, the patrons picked and paid the ladies first. I had never been in an establishment such as this and I didn't have a clue what to expect. I was much younger then so I had a huge erection from the moment I walked in the door and saw topless girls walking around. I watched for a while, and then decided to act.
I don't recall how I selected a girl, but I did, and I paid her, but I don't recall how much. She had large bare breasts, I do remember that (I'm a breast man), and she was wearing a small sequined G-string. The patrons were not allowed to touch the women in any way. She had me sit on an over-stuffed sofa, against the back wall in the main room. There were other men and women around, but no one was particularly watching me and this young lady.
As I sat down, my penis was already erect enough so that it poked out of the fly of my undershorts. In other words, my erection was right under my chino slacks, not protected inside my briefs. The lovely lady straddled me, facing me, and sat down on my lap. Her G-string-covered vaginal area immediately touched the erection under my chinos. The music was loud, and thumping, as if the DJ knew what the music was being used for.
The lady on my lap started to grind her crotch on my chino-covered penis, in time with the music. She really knew what she was doing. As a sheltered boy from the midwest, I found this very exciting. My mouth and face were practically touching her large bare breasts. I could smell the perfume she was wearing. At one point my hands automatically touched her bare buttocks, as if to help her grind unto my erection. She cautioned me, 'hands off'. I took my hands away immediately and said, 'Sorry'. I don't think she'd ever had a man say he was 'sorry' in a place like that.
As worked up as I was, for some reason I had not even thought about ejaculating, and its consequences, but she apparently did. I think she'd had some prior experience with these matters, and I think she could feel the strength of my erection. Her G-string was very thin. Then she leaned toward my right ear and said, 'Tell me when you're gonna cum'. I couldn't believe what she'd said, and I said 'what?', and she repeated it.
That further excited this young man, as the thumping music continued, and she continued to grind her vaginal area on my penis. All while her large scented bare breasts bobbed in my face. I couldn't even feel the chinos in between us, it was like my penis was bare against her G-string. This naive young fella had never had a woman actually trying to get him to ejaculate, and this young lady was definitely trying to do just that. Then I felt my ejaculation coming and I whispered to her that I was going to have an ejaculation in my pants. She immediately rested her knees on the edge of the sofa, and raised her crotch area from my penis. I guess she knew that my semen would soak through my chinos and she didn't want to get any on her G-string.
Yes, I then ejacualted into my chinos, squirting out lots of warm sticky slippery semen. It made a big mess inside of, and partially outside of, my pants. I was somewhat embarrassed, but no one seemed to care, or even notice for that matter!. For some reason, I thanked the young lady who'd done this for me. She smiled, said nothing, and walked away.
I slinked off to the restroom and used tissue to clean myself up. I resolved that I would put a condom on my penis beforehand if I ever contemplated doing this lap-dance thing again.