Although the situation is nonsensical, the doctor's completely detached verbal contribution is insanely hot. I love that the erotic aspect is totally ignored, and that the action is all focussed on the need for a protein injection.
I’d like it better if the patient didn’t know all the details up front. It's only once the doctor is inside him that he realizes what is really going on. And by the end he’s loving it and can’t wait to come back for his next appointment.