How shall I call him?

Team assistant S. and I had our break. We sat in the little kitchen which is for the nurses, the glass door closed to keep away disturbances, noise and everything that keeps you away from your sandwich.
(Not that patients give a bloody shit though. Most of the times someone opens the door (without knocking of course) and says: "Oh right, I see you're eating but could you do (insert random shit here) for me?" In the past, I choked down my food and left the table to do that, but not with S.
She forces you to sit down again and says with a very polite voice: "I'm eating." and if the patient did not get her message (even though there is nothing to be misunderstood) she repeats "I'm eating." This sentence includes the promise: "I will eat you, if you don't fuck off and leave me alone asap!"

But what I actually wanted to write was this:

We sat in the kitchen, the glass door was closed. We talked about this and that when suddenly one of our three Doctors appeared in front of the glass door. He shielded his eyes with his hand, peeking inside, saw us, smiled and started to do the moonwalk and some dance moves in front of the door to entertain us.

I don't have a nickname for him yet. Like for Dr. Mumble in the hospital where I underwent my apprenticeship. I think Dr. Coffee will do the trick though, the German word for coffee sounds a bit like his name and the first thing he says is alway: "Heeeey ladies... Oh, you've got some coffee left! Sweet!" Needless to say, we do get along pretty good.