"God damn it!" He barks, jerking a little at Cas's sudden appearance and slowing to a stop. It's been years since he's done that, been years since Dean's had to deal with the sudden beat of wings in his personal space, and he seriously, seriously doesn't know why he wasn't expecting that when he slammed the door closed.

He levels Cas with the most exasperated, annoyed expression known to mankind, and starts striding off again. "How about you keep your mouth shut about things you know nothing about, huh? How much more clear do I gotta be? I don't want you here. I'm handling it."