[Everything that Crowley wants to say is held behind clenched teeth, but this is a familiar sort of thing. Don't reveal too much, don't overstep, don't go too fast. He can be quiet and patient, waiting for Aziraphale to decide where this is going to go. At least they're not having an argument about it, he's not sure he's in the right frame of mind to handle that sort of thing.

What eventually comes out of the angel's mouth isn't much better, but it's so typical despite it all that Crowley can't help laughing. Fortunately, it does sound more amused than unhinged.]

Oh, you've just decided for us both now, have you? Who says I want to be holding your hand? [And yet, he shifts his grip on the wheel and holds out the hand closest to Aziraphale.] It mightn't wear off. Sometimes these things don't until you've satisfied some mysterious criteria.

[This reminds him of those strange little plant creatures, actually, though that's clearly not the case here.]