Gabriel's not entirely opposed to a little emotion here and there. Anything too sappy will just make him laugh, but his attitude to tolerable levels of emotion tends to depend on the other person. Being in this situation with Castiel is unthinkable, but since Balthazar is actually capable of expressing emotion without using sarcasm, it's a lot easier to just relax and not-quite-cling.

"Me? Awkward? Please. I've never even seen a sense of shame."

But - a dream, yes, that would make sense. He's not sure how he hadn't realised earlier, though now that he thinks about it, he suspects he had. Just never for longer than a few seconds at a time. He hates dreaming, especially when it's a dream with such potentially awkward consequences. He is going to be awkward about it, but at least now that Balthazar has said so he can pretend not to be.