Aziraphale and Crowley are both idiots, with a severe lack of common sense on any given day.
But these idiots were both tasked with watching and guiding the new humans God had created, for better or for worse. What they didn't realize was just how unprepared they both were for this task.
Before being sent out to Eden, they were BOTH given a crash course on the newest creatures, (humans??) roaming around the garden. Just the essentials, don't poke here, this does that, avoid this bit, this part leaks, etc.
Aziraphale's lesson was much more formal, only highlighting the parts of the humans that were deemed 'essential' by the Archangels
Having to sit through Gabriel explaining the purpose of a tongue for hours was enough to make anyone zone out, let alone a principality who had just been told that the place he was being sent to would be full of creatures that were filled with an odd combination of liquid at all times. Good Lord, how was he meant to protect these humans when they could explode at any time?
Aziraphale had checked out mentally by the time they started covering exactly what the eyebrows were for
Hell decided to take a more hands-on approach.
By hands-on, they meant having Dagon draw what they assumed a human might vaguely look like, and then explaining the best ways to torture the squiggly bits
Crowley spent most of the class trying to decide whether the drawing looked more like a horse or a soggy blanket crumpled into a pile
(Crowley had only recently learned about the 'horse' idea, and he was decidedly not impressed by them.)
(He could get behind this blanket idea, however. He'd have to check that one out in a few years.)
So once they'd both reached the Garden, and checked the place out for themselves, they both came to the same conclusion.
They had some SERIOUS questions about what was going on here
Naturally (and reluctantly for one of them), they gravitated towards each other. They both knew asking either of their sides would imply that they didn't pay attention to the classes. And neither of them wanted to have a repeat lesson, thank you.
"Ah, yes, hello, Crawley was it?"
"Obviously, still me. Be odd for me to be someone else, wouldn't it?"
"Yes, well. I was wondering..if you had..perhaps....noticed anything about these humans?"
"Noticed what? They're awfully boring. Told me 'get up there and make some trouble', but all they do is sleep and eat things and walk around. Made 'em trip a few times, but it got old by the 5th time around honestly."
"Well I don't think they're meant to do much more. If they were, then they would have. As is God's plan. Oh there is no need for dramatics Crawley."
It was at that point Crawley sighed VERY aggressively, flopped down onto a rather soft looking patch of grass, and looked up at Aziraphale.
"Was there a point here, Angel, or have you just come to preach?"
"I do wonder, however, if God was perhaps made aware of the issues in the hardware, as it were."
"Yesterday, I saw Eve walking around, admiring all the plants and such. They really are truly beautiful, you know. Have you seen them yet?"
"Nah, haven't gotten over there yet. Mostly been hanging around on the rocks, very warm there. Why? What'd she do?"
"Well, she walked up to the flowers, and..then she just..sort of...." Aziraphale trails off, very hesitant about how to describe the situation.
"Sort of what?" Now Crowley is curious. Always been his downfall, that sort of thing.
"She just... she stuck her face into them."
"Exactly! Stuck her face into them, no warning or anything. That poor, poor woman could have been killed. Who knows what those flowers will do to her tongue."
It was at this point that they both realized that they may not have gotten the same education on the humans and their anatomy.
"So, they aren't actually going to explode? Oh thank God."
"Well, I mean they could, I suppose. If you poked them enough, or shook them up really hard. Y'think we should try that?"
Between both of them, they gathered enough information about the humans to have a general idea of what they should and shouldn't do to help them survive
(Crowley might enjoy watching them trip, but he's a Demon, not a monster. There'd be no point going and killing them right after they launch the whole program.)
It turned out that what they had gathered between Heaven and Hell was quite literally the bare minimum of human physiology.
They stuck together from then on, determined to find out everything they could about the humans.
The first time Eve sneezed after smelling the flowers, Aziraphale jumped up so quickly that he broke the rock he was using as a seat clean in half
Crawley and Aziraphale stood perfectly still on the wall, waiting for something else to happen.
All Eve did was sniff a bit and walk away.
Aziraphale turned to Crowley, eyes wide and full of terror. They both stared at each other for a few minutes before they both silently sat down, contemplating what they had assumed was a very near-miss explosion.
The next day, when Adam stepped into the pool of water at the edge of the Garden, the angel and demon watched with the utmost attention.
"D'ya think they can breathe in there?"
"Yeah, those slimy things at the bottom seem to be doin' just fine without coming up top. Maybe the humans can do that too."
"Crawley, those are fish. The humans need the air to live. I think."
"Fiiiiiish? Fsh. Fiisssshhh. Nah, don't like that. Slimy things works better, who names these things? Was it you?"
"I'm afraid that was not my department, unfortunately. I like to think I would have gone with a different choice than 'fish', if I had any say in the names."
"Mm. He's been down there for a bit, yeah?"
"Who? Oh, him. Has he? Oh. Oh Lord, he has. Adam? Adam?"
One small miracle later, the humans and the non-humans had both learned that they did need the air to live.
The day Eve and Adam laughed together was a good day.
'What're they even laughin' at?" Crowley wiggles/walks* his way over to where Aziraphale is sat on the edge of the wall, watching the humans.
*He's still figuring out the whole leg thing, far too complicated if you ask him
"If I had to guess, I'd say they're laughing at the state of Adam."
"How'd he even get like that? Last I saw, he was running around near that pond, how's that happen? They were on your watch, Angel."
"Ah, while you went to look at the plants, he fell. Apparently when dirt and water mix, it becomes very sticky. Mud, I believe it's called."
"Blegh. Way to go Angel, I left for five minutes and you let him get all mud-ed. Looks awful, don't see why they're laughin'. They've always got somethin' stuck to em."
Despite his words, Crowley couldn't help but smile at the humans. Something so ridiculous and they stood there laughing at it, having all the time in the world to explore and find out new things.
Aziraphale noticed this, and smiled as well. Mostly because of the humans and how fond he was already of them
But also, at Crowley and a new type fondness for him, as well.
(Though it would take many, many years for him to admit that)
Crowley and Aziraphale sat and laughed, watching these new humans bumble around and laugh, being happy to just exist and discover everything there was to discover. If Crowley snuck glances at the angel while he was laughing, he'd never admit it.
Maybe tomorrow, Crowley thought, he'd see what the deal was with that big apple tree.