Dean has about ten seconds to wonder what kind of angel whammy Cas is going to blast him with this time and what kind of effect it might have on his body's ability to function before Cas is touching him and then holy mother of God crap shit fuck.

"Ow!" Dean touches his chest gently through his shirt, but the pain is definitely on the inside. "What the hell was that?"

As he continues to try to soothe a pain that's definitely way too internal for him to get to, he notices that smile on Cas's face. Son of a bitch enjoyed that.