My fantasy involves a female friend accompanying me to one of my regular physical exams. She'd be an outgoing assertive type while I'm quite a bit more reserved, so she'd talk her way into going back to the exam room with me.
I would be instructed to undress to my underwear as usual, and it would be a little awkward having her see me like that, but it's not so bad, right? She's seen me in a swimsuit at the pool, so this isn't that different, and we sit and chat together while I wait.
When the doctor arrives, he would call me up onto the exam table and begin the exam. It would go as usual even though I'd be able to feel my friend's eyes on me the whole time.
At the end of the exam, the doctor would have me stand up for the final parts, making me face directly toward my friend. He'd have me pull down my underwear so that he could check for a hernia and to examine my testicles. Maybe he'd even sit in the chair next to my friend so that I'd have to get very close to them. She would watch intently as my testicles are carefully palpated, unable to hold back a sly smirk.
I'd be humiliated, but deep down I'd get a little exhibitionistic thrill out of it all.
Finally in a fun turnabout, the doctor would realize that my friend is due for her exam as well and that he may as well take care of it while she's there. While I redress, I would get to observe her exam, and it would be extra exciting since she wasn't even expecting it.