It's important, what Dean is saying. Castiel registers that on some level, the same level where his tiny specks of collected Grace hum and yearn to be complete, where memories of flight faster than the human mind can perceive settle and wait to be experienced again. A deep, instinctual part of Cas that will never be different; just as God created humans to be what they are, so did he create angels to fly. Cas wants his wings back too.

But right now, he's still more human than angel, and right now his eyes are focused on Dean's lips as they move. He swallows. Th-thmp th-thmp th-thmp a little faster behind his ribs.