Except it's always messy with the Winchesters. That combined with the fact that Dean has a hard enough time expressing his vulnerability simply means that Sam? Will hopefully not be finding out anytime soon.

Dean waits for it patiently enough, finally exhaling hard as Lucifer slips away from his mouth. Licking his lips, hoping to encourage them back and away from their tingling, Dean lifts his chin to watch Lucifer, mind once more filling with worry. It's all he can do to keep from anxiously staring at the door, instead waiting for whatever might happen next - waiting for Lucifer's final departure. He's fully ready for his break now, to collapse in a heap.

Though, really, the threat of Sam bursting through the door the second the angel leaves is enough to make Dean inwardly panic.