At first I actually thought he was serious due to the expression he had but in the last panel I can see/read he was indeed joking from the start. I must say though, Sally really put together quite the costume, I couldn't even recognize her! Very funny strip.
It's a Halloween-theme right? We don't have that over here, officially (meaning that the stores are pushing pumpkins, costumes etc. big time but very few people have candy ready at the doors).
Frank
