After she disrobed, the doctor began to stroke her thighs. While doing so he asked her, "Do you know what I am doing?"
"Yes," she replied, "You are checking for abrasions or dermatological abnormalities."
"That's right," said the doctor. He then began to fondle her breasts. "Do you know what I am doing now?", he asked.
"Yes," she said, "You are checking for lumps, which might indicate breast cancer."
"Correct," replied the shady doctor. Finally, he mounted his patient and started having sexual intercourse with her. He asked, "Do you know what I am doing now?"
"Yes," she said, "You're catching syphilis, which is what I came here about in the first place!"