Devil's in the Details
This is a short coda to Season One's Dead Man's Blood, when Sam, Dean (and John!) find Elkin's note about the Colt.
Sort of spoilers for season five, and I guess season one.
Starring Crowley.
Summary: The demon's always been their bloody guardian angel, at least when it came to that gun.
His damn pen leaked black blood from the nib to stain the skin of his fingertips. Its ballpoint ran across the page roughly, spitting out words every now and then before running blank. Honestly, he had no idea why he hadn't brought one of his own pens – a demon with such stature surely had enough money to purchase a pen that didn't stop for a rest every third word. He took some comfort in the fact that, had it been human, he would have been tearing its insides out by now. Or at least, he'd have someone ripping its insides out by now.
His lips curled into a concentrated snarl as he wrote. If his handwriting didn't mimic the usual Hunter's Scrawl, it would be obvious to the Winchesters that the note was less than being honest with them. The paper too new? They'd be on to that immediately. Probably have his ass sent back to Hell for his troubles.
Crowley sighed, willing the pen to work long enough to scribble down the very last forged letter. He neatly folded the yellowing piece of paper in half – probably the only sign that this note had been written by anything more than a messy, distracted vampire hunter – and slipped it carefully into the empty mailbox he'd jimmied open.
Once the mailbox was locked again, he slipped into the shadows, disappearing as an engine hummed around the corner. Light flooded the tiny area as headlights swung around the corner, but he was already gone.
Damn doing his own dirty work.