[Dangerous smile? That's where Cas goes from mildly concerned to full on intervention mode. Sam wasn't thinking straight. Cas had to stop this.]
[That fire's kind of annoying--though it doesn't hurt Cas since it's not holy fire, so. He'll just walk right through it to get to the taller Winchester.] That's enough, Sam. [And before there's a reply, the angel presses his fingers against Sam's forehead and sends him home.]