"I dislike that as well." Cas must really dislike it, because he keeps complaining about it. "I don't understand why Father would create humans to be works of art and then include that in the plans. I can't tell if He intended it to be satirical or metaphorical, but either way-" He's edging on blasphemy with that next part, but who cares?! He can say whatever he wants! Human! Free will!

Realizing this seems to empower Cas, and he sits up straight and grips the steering wheel before saying firmly, "It's stupid."