I did once have a similar thing happen, my 21 year old cousin (f) called me, and invited me over for a few drinks, when I get there, there were 4 of her friends (f) all 21-22 playing cards, so I suggested strip poker :P
Well, long story short they beat me, and I was forced to strip and masturbate infront of all 5 of them and cum into an empty wine glass... I found out later that night they used a deck of cards with little markings on the back, so they knew what cards I had at all times