A/N: I posted this for the 2015 Aftercamlann Big Bang back in September after working on it since February or so, and now I'm finally getting around to crossposting it! Basically, this is the fic that Ate My Soul in 2015. I'll try to post chapters frequently since it's already finished, but if you're interested in reading the whole thing straight off (as well as seeing the gorgeous illustrations that whimsycatcher made for it), it's all on AO3 under my jinkandtherebels username.

There will be some spoilers for the end of the series! Having said that, I hope you enjoy!

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Canis, Corvus, Curses

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Chapter One

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Mordred is eight when he stumbles across the bookshop. The painted dragon sign over the shopfront reads Ealdor Books, worn but still legible.

His mum won't let him go in. "The man who owns the place is…a little bit odd," she admits when pressed. Although she adds quickly, "I'm sure he's a perfectly nice old man, but he is very odd."

Mordred can't get more of an explanation from her. She bribes him with ice cream and soon enough he's forgotten all about it.

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At fourteen, he's just looking for a place to hide.

Honestly, he thinks the shop owner's overreacting. He'd snagged a chocolate bar, that was all; it wasn't the end of the world, but damn if the old man wasn't chasing him like it was.

Forget the police—his mum is going to skin him alive if he gets caught. If they force him to go home.

The thought of going home makes his stomach lurch.

Please, he thinks, still running with no direction. All I need is someplace to lay low for a bit. If I can just get out of this, I promise, no more stealing. I'll become a model citizen somehow. It'll be my goal in life to be a productive member of society.

Mordred does this sometimes. It's not praying, exactly, more like making deals with luck or fate or whatever higher power people think governs the order of things. And he's never been one to shy away from something when it might help him get out of a scrape, so here he is.

And the thing is, he'd've quit doing it ages ago, chalked it all up to kids believing in anything and everything and left it behind, except that sometimes it actually works. Like magic.

Like the painted shopfront that he almost runs right past, only realizing at the last second that the place is empty.

He darts through the open doors into cool near-darkness, a bell tinkling softly over his head, the smell of dust and old things filling up his nose.

There's no one here. Mordred lets himself take in a deep breath—

"Can I help you?"

—and nearly dies of heart failure when someone speaks out of the shadows.

This is punishment, isn't it? he thinks irritably at luck or fate or whatever it is. You knew I was lying about becoming an upstanding citizen and now you're trying to off me for it. Great. Thanks for nothing.

He turns around, though, because he's really sick of running. The bookshop employee is standing there with a stack of books in his arms and something about him makes Mordred take a step back.

It's not the guy himself, he's more or less unremarkable—lanky, dark-haired and blue-eyed much like Mordred himself, albeit in possession of a fairly impressive pair of ears—but the look on his face.

He looks like he's just seen a ghost. Which wouldn't surprise Mordred much, in this place, and he suppresses a shudder.

"I'm fine, thanks," he says politely. Shop workers don't call the police on Polite Upstanding Young Men, even when they're definitely meant to be in school, so Mordred's dedicated some time to perfecting the illusion.

"You're…" The man swallows hard. Mordred sympathizes; he can actually see thick clouds of dust drifting around. "What are you doing here?"

All right, congrats Mordred, you've managed to find the one shop worker in the whole of England who actually will call the police on you for being out of school.

"I was looking for a book," he invents wildly. "For an essay. I was wondering if you had anything…"

He lets the question drift off into awkward oblivion, mostly because the man doesn't look like he's listening. He's wearing a red neckerchief, Mordred notices, because how can he not? Who even wears neckerchiefs? Anyone?

Bookshop employees who possibly moonlight as serial killers, apparently, and Mordred's starting to feel deeply uncomfortable with the amount of scrutiny he's getting. Especially since the guy has evidently surpassed shock and is now looking at him like Mordred just killed his kitten or something.

Wonderful.

He's considering just edging out of the shop and hoping the guy doesn't notice, because it almost seems like he wouldn't. But he resolves to try one more time.

"Hey," Mordred says, raising his hands. "Look, I'm just—"

But that's as far as he gets, because the second his hands are level with his chest Big Ears flips the fuck out and raises his own.

The books hit the ground, which registers second to the fact that Mordred feels like he's just been hit by a fucking truck.

I am definitely being punished for something.

He barely notices hitting the floor, barely notices that he's rapidly blacking out, but he does manage to stretch his fast-blurring vision up toward the skinny man.

Gold is bleeding from his eyes, and it's the last thing Mordred sees.

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"Help him," Merlin shouts—pleads, and doesn't care that it's obvious. He has no room in him for posturing or pretending now, not when Arthur is dying in his arms. "I know you can hear me! Help him!"

"Why should we?"

Merlin turns so fast he nearly gives himself whiplash and sees what can only be the new Sidhe elder, bright blue skin and sharp white teeth gleaming in a deeply unpleasant sneer.

The answer comes to him in a burst of terror-fuelled fury.

"Because if you don't, I will destroy Avalon," Merlin swears. "I will pull away its waters and blast whatever remains with fire, and you will have nowhere to turn."

He knows he can do it. He has the power, and, perhaps more importantly, he has the rage for it.

Or he will, at least, if Arthur dies. But that is an 'if' that does not bear thinking about.

The elder's expression doesn't change. "I do not question your power, Emrys. All the same, if we do you this favor, we will expect something in return."

Merlin doesn't hesitate. "Anything."

With a mockingly gracious nod, the elder hovers down to inspect Arthur's wound. It's clean, not festering—Merlin made sure of that a thousand times over—but it's killing him all the same.

"A sword forged in a dragon's breath," the elder murmurs, almost to himself. "Impressive work. Even now the shard winds its way to his heart."

He looks up, sudden and sharp. "I will require a promise from you, Emrys."

"Anything," Merlin repeats, hearing the desperation in his own voice; he doesn't know how much time they have left, but Arthur's breathing is shallow and harsh, so it can't be much.

The elder's eyes narrow. "I will require you to swear that after this deed is done, you will never again set foot on the shores of Avalon. The Sidhe have suffered enough death and destruction because of your interference, and we tire of being summoned like servants to deal with petty human concerns. Swear it."

"I swear."

Those sharp teeth make another appearance. "In blood, Emrys."

Excalibur is still on the ground a scant foot away. Still wet with Morgana's blood.

Merlin shoves the thought away and reaches for the blade, pulls it roughly across his palm and watches his blood spatter across the ground in the dying light.

"I swear never to set foot on Avalon's shores after this day," he intones, steady despite everything in him screaming that Arthur is dying and this is no time for ceremony.

"Very good," the elder breathes. His eyes are fixed hungrily on the blood that stains the grass.

Merlin doesn't have time to question what he just did, to wonder if he'll end up regretting it. It doesn't matter. The elder could have asked for his life or his powers or his soul; the answer would have been the same.

"I will keep my end of the deal," he snaps. "Now do what you've promised. Keep him alive."

The elder waves him off like an errant child. "Yes, yes. I will summon my brethren."

He does, even if Merlin doesn't hear anything resembling a summoning. But he feels something. A shift, a stillness in the air that doesn't seem natural, and a strange note singing in his blood. Reverberating inside his head instead of outside.

And then the Sidhe are with them.

Merlin blinks and they're there, the hazy light that haloes their kind blending together until it's near-blinding. The elder speaks in a language Merlin doesn't understand, and the light gets brighter, brighter, until he has no choice but to close his eyes against it.

When he opens them again, the light is gone. As are all of the Sidhe save one.

"It is done," the elder tells him. "Your king will live."

Merlin actually sags in relief. It's like an incredible weight has gone from his chest, leaving him able to breathe like he hasn't since Morgana trapped him in that cave, powerless and useless.

"Thank you," he manages. "I won't forget this."

The elder waves him off. "It matters not. You will leave us in peace; that is thanks enough. But remember this, Emrys—we do not reverse our bargains."

He's gone between one blink and the next.

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Merlin doesn't know how long he stands there like an idiot after the boy hits the ground, staring at the body crumpled on the floor in front of him like it's going to disappear before his eyes. It's possible. Stranger things have happened.

Stranger things, like the fact that Mordred just walked into his fucking shop.

It's not that he hasn't wondered over the last two millennia about reincarnation and similar ideas. Many insisted that it was legitimate, that it did happen, and Merlin, well—Merlin became a damned cornerstone of mythological pop culture somewhere along the way, so who is he to judge? Once again: stranger things have happened. He can't even remember the number of times he's done a double-take as a stranger walked by, wondering if it might be Gwen or Lancelot or any other number of people—but then, he isn't sure he would even recognize them anymore. It's been…well. It's been a while, and even magically enhanced memory is fallible.

Still. He never thought it would be Mordred.

Slowly, deliberately, Merlin unfreezes himself and sets down the stack of books he's been holding for god knows how long. None too gently, either, as they send up a cloud of dust that makes him sneeze—he really needs to dust in here one of these days—but at least it shakes him out of his shock. Out of habit, he glances out the window.

Ah, damn. The sun is going down. He needs to lock up and get home.

Are you somehow forgetting the passed-out kid on the floor?

Merlin winces. He's pretty sure he's still in shock, or denial, or something, and he's loathe to leave Mordred on the floor when he doesn't even know how long the sleeping spell will last, but he's not exactly overburdened with options.

Normally he would actually walk the three or four steps to lock the doors the old-fashioned way, make a show of it on the off chance that some passerby might be paying too much attention. But he's too rattled for that now, so it's with a careless flick of his fingers and a flash of gold in his eyes that the locks click into place.

He doesn't even stop to count the money in the till; it can wait until tomorrow, and besides, anyone who tries breaking into this particular shop will very much wish they hadn't.

That done, Merlin heads for the door in the back of the shop. Stairs behind it lead up to a reasonably sized flat; he takes them two at a time. His hands tremble as he reaches the upstairs door, making him fumble with the key, and after a few seconds of fruitless frustration he gives up and uses magic again.

The raven is waiting for him when he gets inside.

Merlin lets out a breath he hadn't realized he was holding.

"Hey," he greets, and gets a croak in response.

Merlin's stomach is growling, but he'd been running late as it was and there's no time to make anything now. It'll have to wait. He needs to write this down before—

He looks out of the window again and cringes. Damn.

Not in two thousand years has Merlin managed to lose the habit of picking up after everyone's messes but his own. The flat exists in a perpetual state of what he's dubbed "comfortably chaotic", but even if the world turned upside-down and he was seized with a sudden urge to clean it all, bits of scrap paper and writing instruments would still be strewn everywhere. The way he lives kind of requires it; he still rates the invention of the Post-It as one of the greatest innovations of the twentieth century.

He's pulling an electric blue one off the refrigerator and reaching for a pen even before he's managed to get his shoes off. The raven watches it all from its perch on the back of the sofa, its blue eyes calm.

Merlin spares it a smile as he bends over the countertop and uncaps the pen.

And hesitates.

How in the hell is he supposed to put what just happened into a single blue square?

The fast-sinking sun leaves no time for deliberation. Merlin bites his lip and scribbles out:

Are you sitting down? Sit down. Mordred came into the shop today. Yes, I'm sure, and no, I don't know what it means or if it even means anything. I sort of—Here he hesitates, making a face at the paper. But there's no good way to say it, so: I sort of knocked him out. Didn't know what else to do.

He's running out of room on the note. Merlin grumbles and peels another one off the pad.

I'm not sure when he'll wake up, so don't do anything stupid. We need to think this through.

Merlin hesitates, but he ends up writing 'see you in the morning' instead of 'love you'. No need to incite panic with unsolicited displays of affection.

God forbid, he thinks dryly, capping the pen. He sticks the notes together and puts them smack in the middle of the counter where the recipient can't possibly manage to miss them.

Sighing, he walks over to the raven. A familiar itch niggles at the back of his mind, warning: it won't be long now. He runs two fingers along the bird's head. It nips carefully at the offending digits and he pulls them back, grinning despite himself.

"Fine, fine. Just—look, just don't go berserk on me when you read it, all right?"

The raven's eyes narrow the slightest bit, enough to let Merlin know he's been heard.

And it's just as well, because a full-body shudder hits him, knocking his legs out from underneath him. Honestly, he thinks irritably, you would think I'd be better at this by now.

It's his last coherent thought. Merlin's vision blurs as the raven's shape does the same, growing, remaking itself.

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