The scariest moment of Crowley's life happens hours before the end of the world is set to occur.
It happens in Aziraphale's bookshop, with no angel in sight, and his entire cluttered collection of novels and poems burning and turning into ash.
Crowley falls to the floor an(more)d he shouts to nobody, and for everybody to hear, "Somebody killed my best friend!"
But the only person he wants to have listen to him is dead somehow. Crowley feels the ache in his bones and his heart and his soul-or where his soul used to lay.
He leaves the bookstore with the only book he's ever heard Aziraphale wish for and he goes to a bar to try and forget that now it's just him trying to stop the end of the world. Him! A demon who only cared about one angel and all the things that made them happy.
Crowley thinks about Alpha Centauri, and about the Antichrist, and he thinks long and hard about Aziraphale and how much light and love seem to surround him. He knows he looks like a crazed, heartbroken maniac, and he can't be bothered to argue that because he IS. He was crazy for Aziraphale, and now he is heartbroken for Aziraphale.
He wants HIS angel back, the angel that hides him from the rain and that gets distracted by any mention of food. The angel that he's grown to love, but lost all the same anyways.
Nobody looks in his direction, not even when he wraps his arms around himself (because Aziraphale isn't there to hug him anymore), and nobody says anything when he sobs out Aziraphale's name over and over again.
He's so drunk he's forgotten about everything-the missing Antichrist, the end of the world, Hastur, Beelzebub, everything.