A/N: Because combined Earl Cain/Good Omens is like alcoholic black coffee. Or something.

* Know this: A) Aziraphale has a book shop, but tries very hard not to actually sell his precious books. B) Cain collects poisons. C) Cain does not like his father, for many very good reasons.
** I use earl because I’m told it’s the correct title, though count is lovely and alliterative. Could just use ‘hakushaku,’ but that would befuddled poor Aziraphale.

It was not a dark and stormy night, but it was a rainy afternoon, and the clouds made for a certain dim quality in the lighting. The angel Aziraphale was happily tucked away inside his shop, drinking tea and poring over a pile of recently acquired volumes. He was tired, and snug, and the tea’s warmth provided a very pleasant defense against the chilly bite of the air.

So naturally he was a little displeased when the door swung opened and a dripping, black-cloaked figure walked into the room. Aziraphale set down his tea and his tome with a sigh, and rose to greet the man.

“Oh,” he said, spotting the dark hair and the golden eyes. “Hello, Crowley. Did you want a drink?”

“Crowley?” The man’s voice was considerably lighter than the demon’s. “I’m afraid you seem to have confused me with someone else. My name is Hargreaves.”

“Oh!” Aziraphale peered at him. No, not Crowley. Too young, too—well, feminine. Still, the expression was eerily similar. “I’m sorry. Do come in. Hargreaves, you say?” The name was familiar. One of those noble families; an earl, he supposed. Aziraphale was a noble at present. He found it more convenient.

“Cain Hargreaves,” his visitor replied, shedding his overcoat and stepping into the middle of the room, into the light. He raised his eyebrows inquiringly. “I believe you sell rare books?”

Instantly Aziraphale’s friendly, slightly abashed smile morphed into a grimace of hostility. “Yes,” he said warily. “But I’m afraid we’re closed.”

“You won’t mind if I browse a bit, then?” the boy said politely.

Aziraphale was certain that the flicker of laughter in the golden eyes was not simply his imagination. He wavered, uncertain of how to defend his hoard without being outright rude. Hargreaves took the opportunity to step casually into the maze of shelves, hands in his pockets, with a mocking half-smile on his face. Aziraphale seethed.

There was no hope for his quiet reading with a customer roaming his lair, so Aziraphale stood uncertainly by his chair, studying the invader with a vague furrow in his brow. The boy could not be more than seventeen or eighteen years old. He was slim, aristocratic, with fairly long dark-brown hair and thickly-lashed eyes that upon further inspection turned out to be a curious mixture of green and gold. They made Aziraphale distinctly uncomfortable.

“Do you have anything on poisons?” Hargreaves asked, his hand pausing by a crumbling old book entitled Herbs Fore Ye Olde Dummies.

“No,” said Aziraphale, shortly.

At that the boy looked directly at him and Aziraphale was certain he was laughing to himself. “Really? This one seems to be.” He tugged a slender volume from the shelf and raised it to the light. “Obscure Poisons. Perhaps you overlooked it.”

“Perhaps,” Aziraphale agreed. “Will that be all, Mr. Hargreaves?”

“Earl Hargreaves,” he was absentmindedly corrected, “and call me Cain. If it’s no trouble I’d rather like to have a look at this shelf. It seems promising.”

Aziraphale could not quite bring himself to utter either No, it’s no trouble or Get out of my shop now, fiend. He settled for glaring at the boy’s back. If the wretch tried to buy anything he’d simply say that only browsing was allowed after-hours.

Seconds ticked past, and Aziraphale began to unconsciously flex his fingers, which were itching to snatch his precious books out of the earl’s hands. He cleared his throat. The noise was very loud in the near-silence of the shop. “Are you finished?”

“Finishing up.” The response was airy.

Sourly, Aziraphale stalked back to his chair and settled down with his mug. The tea was very nearly cool. He rose to dump it out, sulkily, and returned several minutes later to find Cain still wandering the shelves. Obviously intervention was required. “Mister Hargreaves—”

“I think this will do nicely,” he was interrupted, and Aziraphale’s eyes widened in horror. The earl held at least five—no, six!—books piled in his arms. “Do you have a bag? I’m afraid I didn’t think to bring my servant.”

“We’re closed,” Aziraphale began, stony-faced, and was blithely overridden.

“Nonsense, there’s no reason to postpone business,” said Cain. “Here’s money for the books—it is enough, isn’t it? I shall come back in a week or two to see if you’ve anything new. For some reason all the other shop owners round here shy from carrying the texts I require.” He looked almost lovingly at the cover of the topmost book, which was entitled Deadly Herbs and Fatal Flowers.

“I can’t imagine why,” said Aziraphale dully, watching the sizeable pile of coins pour into his hands. He couldn’t very well demand the boy put them back. Perhaps if he stared hard enough the money would turn to counterfeit.

Cain stepped toward the door, his arms filled with books and one hand wrapped round a polished cane. He looked uncertainly at the door, and just as Aziraphale was beginning to enjoy the thought of not opening for it him, the handle turned, the door swung open, and a far more familiar dark-haired figure sidled in.

Aziraphale started to say, “Hello, Crowley,” for the second time that day, but the words slithered back down his throat. Crowley and the young earl stood motionless, staring at one another like cats, their faces carefully blank.

“A. J. Crowley,” said the demon, finally. He offered his hand, then remember the boy’s burden and simply nodded.

“Cain Hargreaves.”

“Hargreaves, hm?” Crowley smiled. “Related to Alexis Hargreaves? A good friend of mine.”

At that the boy’s eyes widened, and Aziraphale fancied his face paled. “Pleasure meeting you,” Cain said, and walked rather abruptly through the door Crowley still held open.

Aziraphale was briefly and intensely envious of Crowley’s ability to upset people. “Come in,” he urged, wandering back to his armchair. “How’s the weather?”

“Typical England.” Crowley made a face. “I can’t stand this horrible little country.”

Aziraphale picked up his mug, remembered that it was empty, and set it down again. Crowley settled in the chair opposite his. “You’re a friend of his father’s?” the angel asked cautiously.

“Of course not. No one’s friends with that mental case, and anyway he’s been gone years. I just wanted to see the kid’s reaction.” Crowley yawned, and rubbed his face tiredly. “Crazy family. Death follows them like—like puppies follow their owners.” He was aware that Death did not follow the Hargreaves yapping cheerfully and bounding off after squirrels, but Aziraphale would get the idea.

Aziraphale did. “I see,” he said disapprovingly.

“No one’s ever gotten anything on any of them,” added Crowley, grinning. “Well, that one—what’s his name? Cain? Odd name, that—doesn’t seem to be on the best of terms with his father, and that can only be good.”

Aziraphale was only half-listening. “There have been a lot of deaths recently,” he said slowly.

Crowley shrugged. “There have always been a lot of deaths recently in this area. Like I said. A puppy. Crime everywhere. You’d think half the citizens are serial killers, and the other half incestuous pedophiles—oh, don’t look at me like that.”

Aziraphale managed to rehinge his jawbone. “Incestuous pedophiles?” he asked weakly.

“Not necessarily both at the same time,” Crowley offered.

“Oh dear.” Aziraphale looked mournfully at his hands. “And this century was going so well, I thought.”

“Anything beats the fourteenth,” said Crowley, with feeling. “Anything.”

Aziraphale cast about for a change in subject, and Crowley’s introduction flashed through his mind. “Crowley, what is your first name?” he asked slowly. “I don’t think I’ve ever heard this one.”

The demon blinked and shifted uneasily in his chair, gaze flitting sideways. “Addison,” he mumbled.

“Addison?” Aziraphale’s lips moved silently for a few moments. “Interesting choice,” he said finally.

More than a hint of red darkened Crowley’s stubbornly pale face. He muttered something that could have been “Bugger off” and could have been “Just liked the sound.”

“By the way, dear,” continued Aziraphale, “you really ought to drop the shades. They haven’t been invented yet.”

* A Real Footnote, as in "This is not funny, I just didn't want to bother working it into the story": ‘Addison’ means ‘Son of Adam.’ Which Crowley is very much not. As Aziraphale knows.