This is a sex-stories site! To me, it seems disingenuous to pass a sex story off as True if the sex itself was imaginary and didn't happen IRL. Everyone has vivid fantasies involving the people around them, so it's not like the OP's fantasy is somehow more "True" than everyone else's. Hell, the description (real people, real setup, imagined sex) probably applies to 80% of my stories! But I don't sell them as True.
Having vividly imagined it does not count as “true” in my view, but I guess that’s the post-Factual world we all live in, isn’t it? After all, "literally” got demoted to merely mean “very” twenty years ago, the top trending clips on porn sites now involve obviously fake 18” rubber cocks, and AI-generated porn is quickly overtaking porn involving real, breathing, sweating humans. More seriously, we can no longer distinguish fake photos and video from real, and have progressed from AI applying the Geminio curse to every human-created webpage, whether accurate or not, to us humans laughing it off as "hallucination" when AI regurgitates (or makes up) blatant falsehoods as fact. If insanity is the inability to distinguish fantasy from reality … welcome to the human race in 2026. Here we are now. Entertain us. Do not inform us.
Like AmuseBouche, I don't present a story as True unless it actually happened as I have written it. But even though A Hole New World is my only story in the True genre, because it is the only one that is 100.00% true, that is not to say my other stories don't have true elements. Much of the sex and dialogue in First Love and Dating Daphne are cribbed from past relationships with real women, the part of Lewd Beach where a woman reflexively smiled at me upon seeing my wank-reddened cock really did happen, as did the instance in Daphne’s Bath Accident when a girlfriend accidentally leaked in my face in the bathtub, as well as the moment in Thanksgiving Stuffing when a gay friend suggested I had a nice-looking package. Heck, even the guy and three women in the van in Buff Bluff in Banff directly mirror an actual van clan I encountered on a bike tour, though not in Banff and not sexually (and I did pick up a vibe). So while my stories are mostly grounded in real experience, I almost always scramble not just names, but circumstances and sequences of events, among other reasons to protect everyone’s anonymity - including and maybe especially my own! And to me, even when there are strong factual elements, that kind of mixing is the definition of fiction. Write what you know.
I can’t tell you what to do, and I take a dim view of any kind of formal genre policing, but I do wish you would just put your story in a genre that makes more sense for it.