Aziraphael hums again, a sound that has some translation in actual speech like 'Quite all right, my dear' or some such. Crowley's fingers in his hair are even more encouraging, so he concentrates on trying to keep a steady pace despite Crowley's slipping sibilants.

Abruptly, he pauses, lifting his head and unable to suppress a somewhat wicked grin.

"You know, this is so comfortable... I am getting rather sleepy."