Aziraphale would find himself dressed again before Crowley spoke, waving him to sit next to the demon on the couch. "No games tonight, Aziraphale." He used the Fallen's full name, wanting him to get the point, this wasn't part of the act.
"The goodness that was in me, that you put there, is no longer there. It will dwindle in you, with time, but mine was slight enough to just... dissipate. Without that spark of... whatever, there, grounding me, I could hurt you, now, and feel no remorse." Despite the words themselves, his tone was cold, detatched, as he took another drink.
"You remember what I'm like, after trips Below, Zira. And while I physically didn't go to Hell, it was essentially brought to me. I just need a night." He rubbed a knuckle over his forehead, trying to relieve the pain in his head. He desperately needed to be less sober.