Crowley feels that wanting, the desire for more. He also feels the uncertainty, which brings on it a layer of nervousness on Crowley's part. He can't just seduce Aziraphale and move directly into touching him or making love to him, that might do more to scare him away than anything else. And----careful moment of pause for the fact that Crowley just thought of the whole business as "making love", which should have made him cringe to even think of a term like that, much less as something he'd want to do.

But more. Crowley can do more.

He moves to push the angel back onto the bed and lean over him. He looks down at the angel in this position, then leans down to press his lips to his throat.