I think I might have mentioned this story before, but I once received a 1-star rating from someone simply because my character was not overpowered despite my story having the "Overpowered Protagonist" tag. But just because my protagonist was not overpowered at the time they read the story, does not mean I lied when I added the tag. I just haven't gotten to it yet. In that same vein, that same story also has the "Battle Academy" tag, but as it's focusing on the protagonist's steady aging from birth (and she's currently 10-11 years old) I obviously haven't gotten to that either.
My point is, you aren't baiting anyone if the story is actually going to get there eventually. And if someone wants to read your story simply for the sex, then there are plenty of other stories that showcase it much more prominently. It's just my personal opinion, but the readers who read your story for no other reason than because they like it are far more valuable than those only interested in one element of a story that has so much more in it. Not that readers aren't valuable regardless though.
In any case, you know your story best, which is why you're in the best position to tag it accordingly. As the author, only you have this power. So, please don't feel the need to stress over how others perceive a story that isn't even complete. Trust in your own writing and the readers that trust you in turn, and just write how you want to write.
Those are just my thoughts on the subject though, so I hope I was of some help to you.