Depends on the fantasy I have 😄
I really like the idea of being forced. Like applying to a strange study and being held in a secret complex for a time, having me subjected to all sorts of unusual procedures. No one talks with me, the doctors talk about subject 235 as if I was not in the room and so on (however, I like my forced fantasies to be ultimately benign, so they just would talk about, how they search for the ultimative orgasm and procedures how to achieve it and such things).
But I also like the idea of a gynecological / urological office / clinic, which offers some secret special treatments to an inner circle of patients, who know the secret.
Like ladies going to their special doctors, to have their examinations and then their regular masturbation-therapy. Or things that going on in the back-area / baesment of the spa or beaty farm...
Here I like the fantasy, as someone unknowing of this secret, being subjected by chance to those treatments (confused patient records, walking through the false door, getting confused with another patient - things like that).
In that case it's not really forced (as the doc doesn't know that I don't comply) - also me being me, being compliant with such a procedure would be a matter of a few seconds...