"Oneshots!" Crowley slapped the steering wheel triumphantly. "What?" "That's where stupid ideas go!" Aziraphale took a deep breath. "Now look what you've done, dear." He said wearily.

(set after the Apocalet'snot) Crowley, in a fit of drunkenness, confesses his feelings for Aziraphale. It doesn't go down very well. In fact, it goes about as badly as it could've gone, and before Aziraphale could even try to process his (already given) response, Crowley is gone; vanished into thin air. So, in a very Aziraphale-like manner, Aziraphale does nothing for a while, taking it all in. And then he panics.

Crowley had developed a tendency to "drape" over Aziraphale. An arm hooked around the back of Aziraphale's neck, his head resting on the angel's shoulder. It was rare, at first, but draping on the angel, who gave off a force of warmth, felt like Home. God, Satan, oh fuck it, everyone knew that he wasn't prepared to lose it. (*that* bookshop scene)

Based on the tumblr OTP prompt "lighting up whenever they see each other". --- In hindsight, Crowley should've noticed earlier that he was a bit... overly infatuated with Aziraphale.