Look at heavys hand with the cards. Then look what's directly above it at the top of the photo. Or just look at the top and you won't hafta do that sophisticated and complicated work of reading this comment.
LOLOLOLOLOLOL! Medic: ( Desperately trying to read All Quiet on the Western Front.) Heavy: LADADADADADADALADADADADASANNNNDVICHSANDVICHSANDVICHISFOODFORMEANDSASSSSSSSHAAAAAAAAAAAAAKABOOMKABOOM.......... SING WITH ME DOCTOR! LAHDADADADADADADADA.... Medic: LET ME READ, HEAVY! Heavy: DOKTOR MUST SING WITH ME!
It was structured and done very well. It really does feel like it's a snapshot in time, like someone was taking a picture of it. I think Scout... or Spy... perhaps to use as blackmail to Medic later. But I can see there being some sort of story going on.