Group medical examination fantasy

I have never participated in a group study where I had to strip naked in front of others. I have a fantasy in which I participate in such a medical examination. This is a military medical examination. I'm 18 years old and I'm only in underwear. After another examination, they tell me to go behind the screen.

There are two young men in their underwear and a woman - a doctor. The woman is taking off her rubber gloves and putting on new ones. She instructs one man to take off his underwear. He obediently strips naked. The woman first feels his scrotum. Then she instructs him to take a knee-to-chest position on the couch. The man's face is flushed with embarrassment. With a slight smile, the woman lubricates her finger with lubricant. She inserts her finger into the man's rectum. First shallowly, then deeper and deeper. The man groans in pain.

She then lets him get up and put on his underwear. A man with a very red face comes out from behind the screen. The woman changes her gloves again. A new man comes in and the one in front of me has to take off his underwear. I know that in a moment I will be subjected to a humiliating examination in front of witnesses. I know that in a moment the woman's finger will be deeply penetrating my rectum. I'm afraid of humiliation and pain, but I'm also aroused by it.