In response to this on tumblr: AU idea: Dean and Cas are two world renowned serial killers, and begin a game of cat and mouse, leaving each other messages in their victims, winking/waving at each other on security cameras. Eventually, it's going to come to a head when they both pick the same victim; Sam Winchester.

When it struck Castiel, it dropped him out of the sky. He set down the first place he could find. He stood in a field in Switzerland, swaying on his feet and staring down at his body, dazed by what it had just done. mpreg