The X-men.  Four of them. Something was going on and one of them was convinced to have sex with the enemy due to some confusion or a reverse-psychology ploy.  While it was happening, I was the one having sex.  Then the rest of us realized what she (I) was doing and that it was what the enemy wanted, so we tried to stop her- but it was too late.  I and one of the others went 'inside' her.  It was like a large, human-shaped pinball table of her reproductive organs.  On either side were two rectangular receptacles (Fallopian tubes I guess) with orange and white goldfish in them.  There was a mechanism to open the container which was I guess activated during sex, allowing a black goldfish to swim into the receptacle.  This was the goal of the enemy, and we were trying to find out where the black fish had gotten into.