Dean frowns. He isn't so great at expressing his feelings, and that trait (or lack thereof) has only gotten worse since the start of this event. Remarkable feelings of inadequacy have been swamping him as well, and the instant those words leave Castiel, he bristles defensively.

"...someone."

Castiel has someone. It's a twenty-something year old human with freckles and a bad attitude. How would he possibly need someone else?

"What are you tryin' to say?"