Well, this is a bit different from my first and only other GO fic. I'm still getting my footing, I suppose...

Aziraphale whispers prayers like "hallelujah" and "eli" against the demon's skin, and it smarts like touching a flame: sharp and precise and quick to fade. There is damnation in his blood, or whatever it is he feels pulsing beneath this foreign skin, and the sheer blessedness of being pressed against Aziraphale is so good it makes him ache.

Humans, he thinks disjointedly, have no concept of Good, no way of understanding what something untainted looks like—feels like. Crowley was Good, once. He remembers it like a dream upon waking—faded and alien. A hollow memory. It's so distant that he can't say he misses it, exactly, except for moments like this, moments when he feels it in the pain of his flesh. Moments when he sees it in Aziraphale's eyes. It is like finding salvation but discovering it is forever just out of reach. He feels a sudden stinging sympathy for Adam at the untamed edge of Eden, for Moses on the peak of Mount Nebo, for Tantalus beneath the fruit tree. And it's worse than any hell fire, because for all the pain, he doesn't want it to stop. The longing builds by the minute, by the millennium, but he can't bring himself to end it. And he thinks that, for this, God is more cruel than any torture in hell.

But the pull of hell is not weakened by any means, and Crowley, for his part, is every bit the demon he is expected to be. Something dark and smoldering, quiet and powerful, that hides in the crevasses and corners of his being, something wants to corrupt. He wants to desecrate the pure and precious thing who's lips are crawling across his neck (and now his chest, and now his hips.) He wants to make this angel, this perfect creature, suffer and writhe, become cynical and unwanted. He wants these things unwillingly, like a man possessed. He wants these things because ultimately, all Crowley wants is to possess him.

All at once, the lust and greed that have simmered in Crowley's chest, since before the beginning of this dirty rock they exist on, boil over, seize his senses and slay all rational thought. With shaking hands, he pulls the angel upwards, biting hard on those red and shining lips, his own forbidden fruit. But what punishment could he possibly suffer?

Here, here, here, here he whispers, pulling at the angel's trousers. Aziraphale lifts his hips, a gesture of submission that makes Crowley's body throb and ache, a deep, liquid heat that rises in the gold of his irises, simmers in the bottom of his stomach. With deliberate fingers, he traces the lines of the angel's body, the angles that shimmer with divinity, the dark corners he can corrupt with his touch.

He wants to be inside Aziraphale in a way that mortals can never be. He wants to tear him open, see what scriptures are carved into his bones, and devour his soul. Crowley shudders at his own longing, but he can't stop it, won't try. With painful control, he turns Aziraphale around, presses the angel's body onto the bed. He hears Aziraphale breathe, slow and deep, so trusting. In a slow, forceful motion, he presses into him, holding the angel's head down, because he doesn't want Aziraphale to see his eyes (wide and bare, drowning in loss.) His lips find the back of Aziraphale's neck, salty and slick, while his hips thrust violently. There is no worship in these motions, no charade of divinity, Crowley will not allow it. It is primal, inherent in the species they inhabit, and it is dark. The selfish lust, the way Aziraphale grinds against him and twists his fingers into the sheets. The way they both growl and moan as the rhythm of their hips speeds up, grows erratic. It does not sound like heaven. It does not feel like hell.

It's human. It's nothing to do with the war between their respective sides, or the eternal, ineffable conflict that means they can never be as they are now—together. It's the pulse of their bodies channeling eons worth of want. It's the thrumming, subtle frequency of their limbs expressing the inhuman desires of their souls.

Aziraphale throws his head back, hair like a shower of gold and Crowley grabs it. The angel's mouth opens, he screams—a painful sound of release and resignation, of damnation. It is the same sound Crowley thinks he made when he Fell (he thinks because he can't quite remember, doesn't want to remember.) The body against his shudders and tightens, and Crowley feels himself give over.

It is strange, living in a body that is not one's natural form. Some times, it feels like operating a machine, with degrees of detachment and clumsy numbness. Even sex is not consuming, not enough to connect Crowley completely with the twitching muscles and firing nerves he inhabits. But right now, as he feels his human body falter and empty itself, Crowley feels, for the first time, perhaps, like he is his body.

They fall forward, slumping against the bed, all sweat and shadows.

In the still, silent afterglow, Crowley runs his fingers through the angel's hair, soothing the quivers and twitches of the body beside his. Aziraphale look up at him, eyes wide with doubt and a gaping need for reassurance. The hellfire in Crowley's mind tells him to laugh, to push the holy creature away and claim his innocence with callous disregard. That is what he should do. What he ought to do. Instead, he presses his forehead against Aziraphale's and says nothing. He is betraying his nature, his purpose, and he will suffer for it, but isn't it worth it? When it comes to a choice between his own continued torment or the damnation of the only being that shines light in the darkness of all of hell, is it really a choice? It's an inevitability. It is a knowing sacrifice.

Aziraphale smiles and breathes against Crowley's skin. This time, it feels like the wind felt in heaven. This time, it doesn't sting.