“You don’t,” Dean starts to say, but the words clog up in his throat before he can get the rest of them out. He stops, and suddenly he can feel every breath going into his lungs, every twitch of muscle as his fingers curl listlessly at his sides. If he listens hard enough, maybe he can even feel the blood rushing to his head and his heart pound against his eardrums. And if he bothers, maybe he can even hear every instinct rattling through his bones and screaming no.
Cas stands there before him, ratty sweatshirt–where did he even get that, what happened to the trench coat–zipped up and his hands buried in the pockets and Dean’s never seen Cas look so small, curled in on himself and trying so badly to mask how hurt he is. This is the expression that accompanied the devastation of Heaven, the decimation of angels, tearing apart the cosmos and Purgatory–this is the expression of Dean telling him to leave. This is his response to Dean rejecting him.
And yet, Cas stands there before him and waits for him to finish.