I had a similar situation. I was in a restaurant, and this guy and I were talking while I was waiting on my order. He seemed okay, so I gave him my cell phone number. He and his friend walked me to my car, and when his friend saw that I had a stethoscope hanging on my rear view mirror, he asked if I was a nurse. I told him that I was actually in nursing school. The guy, Ron (I think that was his name), then proceeds to say "So that means you know how to take vitals signs and stuff". I said yes. So he says..."
So that will come in handy when we are, you know, doing it, you will know when I am about to cum because my heartrate will increase!"
NO JOKE...I said "How about you give me back my number!" He started laughing and is like "No I am gonna call you!"
Since my cell doesn't have call block (that I know of) either, I just plugged his home/cell number that he gave me under
DON'T ANSWER so that would come up on the caller ID anytime he tried to call! Otherwise I don't know what else to tell you!