I always wanted me and my girl to be stripped naked and tied up, feet in front of us and arms above our heads, blindfolded, in a public setting, possibly a music festival like burning man or something. Like in a tent or something. We'd be sitting facing each other, with her on my lap and me inside hers. We're blindfolded but we know a sign is challenging people to tickle our feet to make us fuck. It would be like a dollar per minute. The first person to make us snitch on each other's other ticklish spots would win $20, and the first person to make us cum would win $50. Of course, the line is as long as the line is and so after a minute to process the orgasm, the others in line would still be torturing us to hysterics to get their money's worth.
Another fantasy is inspired by Mantis's story Fair's Fair, where me and my girl are stripped and locked in stocks inside of a carnival caravan, with our bare feet poking out and our toes tied back. We're seated in seats that spread our legs and raise our arms and while a woman acts as a barker outside selling time for the carnival patrons to tickle our trapped feet, another woman is inside tickling, teasing, and turning us on until the timer runs out an hour or two later. By the end of it, my girl and I are so turned on that we fuck each other like animals upon release.