[ Dean sasses him, again, and Castiel pauses the motion of his hands to look up and stare at Dean in narrow-eyed disbelief. Of course Dean's anger and frustration are justified, but Castiel is sure he's never met someone so shamelessly irritating. ]

I'm trying to help you. But my capacity to do so is limited, because you decided to attack and fling shit at the people who brought you food. Would you even have let someone near you if they'd offered to treat your leg?

[ Castiel continues to clean Dean's hands as he argues, wiping away grime and stink as the soapy water grows darker. His strokes remain gentle but they're longer pulls than before, with more pressure, finding more purpose in his distraction. ]