A couple of versions of a sketch. Feel they might need some trimming and refinement.
1)
THERAPIST:
So, I understand you're a little depressed.
MAN (OOV):
It's these new regulations at work. I have to ask so many questions…Have you got AIDS, are you pregnant…have you had acupuncture in the last 6 months, for f**cks sake? It used to be so much simpler. I'd turn up, take blood, they'd go home. Now, they all sod off by the time I get to the anal sex questions.
THERAPIST:
Tell me about it. Apparently you need qualifications to do this job now…err…anyway, you might have Seasonal Affected Disorder. It's easily cured by a bit of sunlight.
MAN:
I work night shifts.
THERAPIST:
Now, now, that's no excuse. Here, let me help you. PICKS UP A REMOTE AND PRESSES A BUTTON. THE BLINDS SLOWLY OPEN. CAN NOW SEE IT'S A VAMPIRE ON THE COUCH.
VAMPIRE:
Oh, shit.
CUT TO A SMOKING CLOAK ON THE FLOOR. THERAPIST PICKS IT UP AND SEARCHES IT.
THERAPIST:
Not again! The bloodsucker never brings any money.
2)
INT. DARK ROOM.
THERAPIST:
So, I understand you're a little depressed.
MAN (OOV):
Yes. I feel lethargic, my skin's pale, my teeth are bad. I haven't fed for a week. My peers all laugh at me. I used to be so strong. It's so…embarrassing.
THERAPIST:
It sounds like you have Vitamin D deficiency. That's easily cured – Sitting out in direct sunlight for 20 minutes a day should do the trick. PICKS UP A REMOTE AND PRESSES A BUTTON. THE BLINDS SLOWLY OPEN. SUNLIGHT STREAMS IN. CAN NOW SEE IT'S A VAMPIRE ON THE COUCH.
VAMPIRE:
Oh, shit.
CUT TO A SMOKING CLOAK ON THE FLOOR
THERAPIST:
Ah. He didn't mean lawyer when he said bloodsucker then.