'Natch,' Crowley agrees, and then, slightly less eloquently, 'Hnngh' when Aziraphale dives right in, so to speak. His buttocks would clench, except he hasn't got buttocks at the moment, so instead he simply experiences a brief, all-over writhe.

'You knew I was a snake,' he says as soon as he catches his breath. 'Just never thought about the implicationssss. You, uh, don't need to pay attention to them both. It's a one-at-a-time sort of thing.'

He's in constant motion now, his hips shifting against the boat's floor, tail constricting and loosening in turns around Aziraphale, his hand around Aziraphale's cock, thumb toying with the head. And, feeling a little less awkward about his genitals, given Aziraphale's (remarkably unsqueamish) interest in them, he looks up with his glowing golden eyes and gives a grin the flashes his forked tongue. 'Ssssso? Thiss is your little fantasssy. Whaddayou want me to do?'