This happened in my senior year in high school, a few months before I graduated. There was a time were my ex girlfriend (who knew about my tickling and armpit fetishes) used to flirt with me while she was dating someone else. She would raise her arms above her head in a big, exaggerated stretch whenever I was around, leaving her smooth pits exposed. When she "caught" me staring, she'd pull her arms down and pretend to scold me for looking. Eventually it got to the point where I would just start tickling her whenever she did it. She would giggle and tell me to stop, but would always keep her arms held in the air for 10-20 seconds and let me keep tickling. This was in public, too. My friends obviously didn't know about my fetish, but it was clear that we were flirting.
It was insanely hot: She would even tickle me a bit sometimes, letting me get all aroused until I couldn't take it and would lean in for a kiss, before pulling away and lifting her arms up again, putting them inches from my face and telling me I could look, but not kiss them like she know I wanted to. We would literally both leave class at the same time, duck into a closet or empty corner of the hallway, and just tickle the shit out of each other. It was interesting, because in our relationship she had been 100% submissive. It's like it took her finding a new boyfriend to discover she liked tormenting me.
Speaking of her boyfriend, he heard what was going on pretty quickly. Rumors swirled around that he was thinking about trying to fight me, and that he was essentially pleading with her to not let me tickle her in public anymore. I wasn't scared of him in the slightest (he was a skinny, short guy, and even though I'm not juggernaut, he just wasn't threatening enough to take seriously). He would kinda glare at me whenever we passed each other in the hall, but that was as far as it went.
It was kind of a bizarre situation; obviously the boyfriend was left feeling humiliated and jealous, and he was kind of taking on the role of "tickle-cuck" in some small way. And yet, he was the one dating/ presumably fucking her, and she never did outright let me do anything romantic with her while they were together. In effect, both of us were kind of being pathetic and strung along (not really the point of this story, but she eventually left him and started dating me again, then broke up with me and started dating my friend, then broke up with him so we could be fuck buddies again the summer before college. So...yeah. This girl was something.)
Anyway, I think a similar situation would be incredibly hot to play out now. Almost a dual tickling cuckold, where the husband knows his wife is being tickled by another man, but the tickler is just being teased without hope of ever fucking his ex.
