[Castiel's eyes narrow in frustration at the laughter, and he bristles more at Lucifer's suggestion of terms.]

I can't convince Crowley of anything. But he is he only one threatening retaliation that I know of; I will not act myself unless Michael--Erik--proves a threat to anyone else.

[Or goes too close to someone he cares about. Same difference.

He isn't touching the suggestion of moving in. Lucifer's insane to propose it as far as Castiel's concerned.]