In 2001's Frailty, the father and son are tasked with destroying demons, after the father has a visit from an angel. When they slay a demon, there is never any blood, on the weapons, or their clothing, or anything. No splatter, nothing shown. When they dig the graves, they are sweaty and dirty, but never bloody. However, when Fenton gets the sheriff and the dad is forced to kill a man (not a demon) the blood is everywhere. On the axe. On the fathers hands and shirt, even on Fenton's face. It not only distinguishes the demons from the men, but may also be another mechanic of their divine protection, as the father says "when we are God's hands, we cannot be seen", or something to that effect.
Little Movie Moments 
