Maybe it's the supernatural creature that was rooting around in him for months, or maybe it's a new and even darker strain of paranoia, but Dean's skin prickles well before the knock, heart beating hard in his thin chest. There's a gun at his side, once an old standard and freshly out of retirement, and it's weight is a comfort. Dean squeezes hard around the metal when a shadow settles in front of his door, but doesn't jump for the knock.

"Who is it?" he calls, hesitating on his way to the door even as his thumb clicks a round into the chamber.