I'm guessing this one deserves more explanation than just "Stilton is on some pretty heavy pain medications at the moment." I've had this piece of clipart that, to me at least, looks like Humphrey Bogart as a milkman. But what could I do with it?! Then I discovered I had an almost identical picture of a milkman who, frankly, looks like Bud Abbott of Abbott and Costello.
So the gag here is that the guy can literally change his face to look like Bogart, but the REAL gag is mostly for me because it was a fun use of clipart. And did I mention the heavy pain medications?