Author's Note: This is a story inspired directly by City of Bones, and it takes place in the same universe, following a different elite group that kills a specific kind of demon. Most of the lore I use here is taken from Celtic and Anglo-Saxon mythology.

Cassandra Clare owns the original series and any resemblance to her characters is intentional.

Congregation of Vapors

Chapter 1:
OPHELIA

The sun hung alone in the sky like a giant incandescent lightbulb without a cover, casting its hazy illumination upon the festival and throwing long shadows from every available surface. Hundreds of excitable, perspiring people were milling around in its balmy radiance, traipsing throughout the sprawl of squat buildings and striped tents. Everything seemed exaggerated in the late afternoon light: the colors richer, the assorted chatter and squeals louder, the smells stronger, the sense of human vitality more poignant.

The creature lurked in the meager darkness, darting around from shadow to shadow so as not to be seen, melting into outlines of its potential victims. And it was hungry… But which human would constitute a suitable lunch? Someone who could be lured into the creature's domain, the nearby lake, to be dragged under by shadowy, unseen hands and devoured…

Azure-colored velvet suddenly caught the attention of the creature, looking very much like water under a full moon—a site of immense power for its kind. It was nearly impossible to resist such a nostalgic lure. The velvet made up a full-length dress, draped around the figure of a beautiful woman in the flower of her youth. She was seated pleasantly on the banks of the lake, uprooted wildflowers scattered around her as she wove what appeared to be a floral wreath to adorn her shining red-gold hair. Perfect.

So perfect, in fact, that the creature failed to recognize its error in venturing out into open, sunny territory with few shadows to hide in…

Priscilla Fracas stormed away from the rickety wooden stage, seething with rejection and the righteous burn of anger. Behind her, the costume contest was still progressing, if the roaring applause of the idiotic audience was anything to go by. But she didn't care anymore. The audience members were the judges for the costume contest, progressing or rejecting contestants as they saw fit, and Prissy had been shockingly eliminated in the second round. Clearly these plebeians were not as cultured as she had anticipated. Her costume was flawless and beautiful! She was drowned Ophelia, for fuck's sake! She had spent hours this morning on her makeup for this!

"Stupid, uncultured, fucking half-wits," she muttered darkly to herself. "They wouldn't know a good costume if crawled up and bit them in the ass!" Prissy knew deep down that she was making a fool of herself, gnashing her teeth and glaring at everyone in her unbridled fury, but she was too far gone to care. As she fumed, she noticed that most of the people standing even remotely close to her were frantically moving out of her way. The observation both pleased and irritated her.

Thoroughly pissed and having a sudden urge to drown herself in ale and mutton, Prissy started heading in the direction of her bored-looking but nonetheless attractive friend Ezra, who was breaking the faire's rules and messing around on his phone.

"I can't believe you're playing Candy Crush at a time like this," she grumbled loudly as she approached him.

"I'll have you know that this game is Panda Pop. There's a crucial difference," he said with forced casual lightness, glancing up at her flushed face. "Tough break on the costume contest. I was clapping for you."

"Clearly you weren't clapping enough," Prissy accused gruffly.

Ezra pursed his lips, still looking faintly concerned. "Relax, Pris. It's the way of the world. Most people are stupid and can't recognize true talent when they see it, and will instead default to whatever everyone else seems to be doing. You can't win 'em all."

Prissy crossed her arms and retorted smartly, "I wish I could." She knew her voice was still too raised for a casual public conversation, but she wanted everyone around them to know how she felt about this setback. "After I put so much work into everything, too."

"Much more than I did, anyway," Ezra said with a sudden, adorable grin. He had merely repurposed most of his beloved Link cosplay for the occasion, and the telltale pointed ears were sticking out from his auburn hair in a distinctly goofy fashion.

"You look like the love child of Peter Pan and Tinkerbell." She said the statement clearly and confidently, hoping that everyone around her would appreciate her wit in a time of personal crisis.

"And you already told me that on the way here."

Prissy furrowed her bold eyebrows even more than they already had been. "That's beside the point," she said at a much lower volume, hoping that no one had heard his comment. She sort of hated Ezra's 'devil's advocate' routine sometimes, even though it was also kind of endearing under less trying circumstances. Ezra was just cute and infuriating in general. Prissy's frown intensified upon realizing her train of thoughts. Now is not the time for this, she ordered herself mentally, her eyes still wildly focused on Ezra's delightful, elfin face and ridiculous false ears. She thought again about her elimination. "I think that all of these uneducated sheeple probably didn't understand my costume."

"Technically, the audience of Hamlet never does get to see drowned Ophelia directly," Ezra pointed out unhelpfully. "It is kind of an obscure costume."

"Obscure?" Prissy ranted, gesturing madly at the period-accurate light blue and gold dress that her neighbor, Brunhilde, had made her. "I'm a fucking Millais painting in real life! Isn't anyone familiar with classic art anymore? At the very least, they could assume that I'm the ghost of a drowned princess, for fuck's sake!"

In her peripheral vision, she saw a mother shielding her small child's ears and giving Prissy a dirty look. She felt validated and only slightly guilty for making such a spectacle.

"Maybe it's because your hair is drying," Ezra suggested, gesturing at her once-damp, waist length hair. "No offense, but it kind of ruins the effect."

Prissy suddenly stamped her foot in frustration, and then took several deep breaths to center herself. "I need to clear my head," she murmured darkly. "I'm going for a walk. Don't follow me."

"Fine. I think I'll get myself some mutton, and then I'm going to chat up that ridiculously good-looking minstrel we passed earlier. I'm such a sucker for a man with a lute," he said, a dreamy expression melting across his face.

Prissy rolled her stormy gray eyes at Ezra's ridiculousness. "Yeah, whatever. I'll meet you at the joust later, okay?"

"See you then!" Ezra called after her elegant, retreating form. By that point, Prissy had already taken off, striding decisively through the crowd of idiots and occasionally elbowing people out of her way. Although she was walking, her eventual destination hadn't been decided yet. She knew there was a lake nearby from previous years' faires… And what better place was there for a drowned Ophelia?

Her mind made up, Prissy began to walk toward the lake, not knowing what darkness was transpiring there at that very moment.

Jett McFarland and Alonzo Fairgrove lay in wait behind a copse of trees, staring at the otherworldly, sinister-looking lake where Tanaquil, Alonzo's sister, was weaving a yellow and white flower crown out of agrimony and cinquefoil that the three of them had picked earlier. She looked suitably classical and picturesque, which would hopefully lure in the Fomor that had corrupted the tranquil water of the area.

"It's a good thing that she's facing the lake," Alonzo whispered to Jett with the same conspiratorial humor that his friends and relatives had come to expect on a regular basis. His playfully roguish appearance was only enhanced by the ceremonial cobalt-blue war paint that had manifested in a spiraling half-mask, making him look like a young, Celtic Phantom of the Opera. "That way, it can't see her face."

Jett half-smiled, seeing from their oblique position relative to the lake that Tansy's expression looked positively bored and murderous at the same time, accentuated by the three jagged stripes of blue paint across her countenance. She hated being bait, but the Fomori had very singular taste and she fit their aesthetic the best. "Yeah, that might throw things off a bit." His eyes swept over the clearing in front of them, searching for anything out-of-the-ordinary. Any moment now, the Fomor would reveal itself… "Do you see anything?"

"Not yet," Alonzo replied, also keeping close watch over the area. "But it can't be long now." A few quiet seconds passed, with only the assorted sounds of the forest breaking what would have otherwise been silence. Then Alonzo sighed. "I'm bored. Remind me why this always takes so long?"

Jett shot him a brief, disapproving look, tearing his gaze away from the clearing for only an instant. Anything more than that, and he might make the crucial error of missing the Fomor. In the sparse daylight filtering through the warped, winding trees all around them, Jett looked just as sylphlike and beautiful as Tansy, perhaps even more—not that he would ever recognize it, of course. "Patience, Lonnie. Any time now…"

"I see it," Alonzo murmured frantically, pulling out his shuriken from inside his tight leather vest. "It's about to reach Tansy."

Jett peered at the scene, his own hand fitting around the shaft of his gilded trident and readying itself for action with practiced ease. Surely enough, there was now an impossibly dark, fluid-like figure crawling towards Tanaquil at rapid speed. Their plan had worked, as it usually did. "Let's go." But something was critically, woefully different… An inexplicable, uncontrolled factor had just arrived and was threatening to ruin their entire mission. "Wait, who's that?"

Alonzo swore and looked like he was about to bash his head against a tree. "A normie. Just what we need at a time like this. What should we do?"

Jett thought frantically about what to do and raked one hand through his long, sandy blond hair to help himself focus. Should they proceed, or would it be better to wait it out just a little longer? He sighed, stressed about having to make such a quick and layered decision, and determined that inaction was the best policy. "Give it a minute. Let's leave it up to Tansy." Next to him, Alonzo nodded in uncharacteristically silent agreement.

Unaware of the dangerous situation she was getting herself into, a normal young woman was walking towards Tansy at the edge of the corrupted, eerie lake…

Prissy found the lake with little trouble, even though she had to pass through the densely-packed outskirts of the festival and wind through a small forest to get there. She felt like the protagonist of a medieval romance, a beautiful young woman forsaking the bustle of everyday life and heading into the wilderness for some clarity. Even her gown was a perfect addition to the fantasy, transforming what would have ordinarily been plain Prissy Fracas into Princess Priscilla.

The shaded canopy of aged trees looked like it had been lifted from a storybook of enchanted tales, where fairies lurked inside every toadstool and magic was afoot. Prissy had always loved trees, feeling strangely at home beneath their antediluvian boughs in a way that her dull townhouse simply could not compete with. She reveled in the sounds of leaves crunching below each footstep, the skittering of squirrels, the rustling foliage from unseen creatures. Each breath brought in the smell of sweet sylvan air, earthy and lush.

She was strongly tempted to stay in the woods, darting between umber-brown trees like a dryad, but then she remembered her true motive in taking this unusual path. The lake, glimmering like a silvery mirror through the trees, winked at her from a distance, drawing her forward. Immediately, her romanticization of the forest faded as completely and effortlessly as a dream, and she forgot everything beyond the beautiful water ahead.

As she stepped into the clearing that surrounded the lake, Prissy's rapt fascination found a sudden interruption: there was a young woman sitting along the lakefront, looking just as effortlessly beautiful as Prissy had always wanted to. Although her back was turned, the mysterious girl seemed like she had been plucked out of a painting by Waterhouse or Rossetti, with her pale skin and incredibly long, Venetian blonde hair. And her dress… Prissy had been immensely proud of her own until that moment, upon seeing that the other girl's was a historically accurate gown of deep azure velvet that hugged and enhanced her lissome figure to an almost unfair degree.

A wave of jealousy flared in Prissy's stomach, but she quelled it easily. She reminded herself that she looked beautiful, too, and that everyone at the festival had seemed impressed with her costume (outside of that farcical contest, anyway). Maybe she could befriend the strange woman… She had always wanted a female friend to reenact her medieval fantasies with, and this girl seemed to have a sense of style, at least… And maybe she was lonely, since there didn't seem to be anyone else around…

Before long, Prissy found herself a mere few feet away from the other young woman. She noticed that there were yellow and white wildflowers scattered around her, which only enhanced her sense of being in a painting come to life, and was about to introduce herself when she abruptly caught sight of a spindly, sinister shadow moving independently along the banks of the river. It wasn't attached to an animal or person, and nothing normal moved like that, slithering and crawling—

Just as Prissy raised her voice in a bloodcurdling scream, mayhem broke out. The girl suddenly turned around, faster than Prissy would have considered possible, and revealed that her face was covered in three blue streaks of paint as she reached underneath her dress and pulled out a wicked-looking gilded axe. At that exact moment, two young men, each wearing plaid and with blue paint on their faces, ran at breakneck speed toward them, brandishing weapons made from the same gold material that reflected the afternoon light in glittering sunbursts. One of the newcomers was holding a giant net, which he threw over the shadow. It began thrashing around, clearly trapped, while the other young man raised a trident and poised to strike.

Prissy's brain didn't know what to think or how to process the scene, and she found that she had just continued screaming the whole time. She grabbed at her face in horror, which somehow threw her off-balance and sent her falling into the silvery lake water.

Before she could perceive anything else, she was surrounded with darkness, and invisible, slimy hands struck out at her and began dragging her underwater. Her air supply was cut off, mouth and nose filling with foul water, and her only panicked thought was that she was about to die.

But then, a trident was plunged into the water, wrapping itself in her lengthy skirt and fishing her out as effortlessly as one might remove a leaf. She was cast onto the shore, coughing and sputtering, and came face-to-face with a hopelessly beautiful young man, his long blond hair falling all around them both like gleaming curtains.

"Are you okay?" he asked, gently seizing her shoulders in his hands and bringing her into an inclined position on the ground. His eyes were just as piercingly blue as his face paint, which was covering most of his face in a way that made Prissy think of Braveheart.

Prissy coughed more in response, spitting out the fetid lake water. Just beyond the barrier of her savior's shoulders, she could see the other two people standing over the net, which had a fully-formed shadow creature inside. Whereas before it had merely been a normal shadow on the ground, it had transformed into a being of a strangely solid kind of darkness and was approximately the size of a Great Dane. The girl was chopping at it with her axe, while the boy threw several shuriken into the being, one after another. Prissy put her head back down to the ground, only to have it tenderly raised again.

"You need to keep your head up. It'll make it easier for your lungs to expel the water," her rescuer explained in a sweet, soothing voice. She nodded to show that she understood, still coughing up water and struggling to breathe normally.

At that moment, Prissy saw the shadow creature dissolving into black mist out of the corner of her eye, the net gently falling to the ground to punctuate its disappearance. "What—what was that thing?" Prissy choked out, her voice ragged. "Is it dead?"

The young man's brow furrowed, and he tilted his head to the side. "You mean the shadow?" he asked tentatively.

"It was more than just a shadow," she responded laboriously. "Didn't you see it? It was like nothing I've ever seen before, so dark and creepy… Do you know what it was?"

Her companion now looked positively worried. "Guys…" he called over his shoulder to his friends, one of whom was folding the net while the other stood beside the lake. "I think this girl saw the Fomor, not just its shadow."

"What?" asked the girl, the now-folded net in hand. She stalked up to where Prissy was lying and glared menacingly down at her. "Jett, what do you mean she saw the Fomor?"

Prissy coughed again. "If you're talking about the shadow monster, I definitely saw something corporeal inside that net." She looked up at the young woman with as much waterlogged defiance as she could muster, trying not to feel ridiculous.

Jett brushed her sopping bangs back off her forehead, his eyes locked penetratingly with hers. Prissy noticed that he was wearing a plaid cloak pinned over his right shoulder, as well as a gray tunic and saffron-colored pants with boots. She found that it was a very attractive outfit, drawing her attention to his lithe, athletic form. "Are you sure that you didn't just see a shadow on the ground?" he asked her.

"Of course I'm sure." Without warning, Prissy suddenly sat up and got to her feet, feeling suitably recovered from her near-drowning. She was usually among the tallest people in any given room, so she was surprised to find that only the girl was shorter, and by a few inches at that. Both young men were astonishingly tall, compared to the general population. And not only were they tall—all three of them were also blond (Jett's hair being sandy and the other two more of a strawberry) with unusually long, flowing hair. And then there was the blue paint, which Prissy suddenly realized extended onto their arms and necks as well as their faces. Were they just dressed up for the renaissance faire? Or were these three exceptionally attractive people part of some Celtic organization?

Breaking the silence, Jett suddenly turned to face the guy near the water. "Lonnie, we should do the ritual now, before the fear spirits realize that their father is dead."

"In front of a normie?" scoffed the girl. "Jett, are you insane?"

Jett stared pensively at Prissy, which made her stomach feel suddenly full of butterflies. "She could see the Fomor," he said simply. "We may as well."

The other guy, Lonnie, shrugged. "I guess you're right," he agreed, falling to his knees and extending his arms out over the water with his eyes closed. "O Lady Viviane, resplendent aquatic all-mother, I implore you in the name of Jethro to cleanse this water of all impurities that are banished in your shining sight to the dark land from whence they came," he recited with practiced but nonetheless passionate eloquence.

As Prissy watched, a glowing, metallic sheen swept over the lake, leaving behind countless spirals of black vapors. Those, in turn, eventually dissipated to reveal a placid, luminous lake that was even more beautiful than it had been before.

All of this was almost too much for her to bear. "What just happened?" she demanded. "First I nearly drown, then you people kill something in a net, and now this weirdness? Am I going mad?"

"Yes," said the girl. "Now please go home and never think about today again."

"Excuse me?" Prissy yelled, growing increasingly angry. "Who the fuck do you think you are, telling me what to do? I've had an extremely traumatic day, I'll have you know, thanks in large part to all of this." Her hand flew upward to her neck to hold the amulet of her beloved necklace, as had been her nervous habit since childhood, only to find it missing. Unable to help herself, she screamed. "And now my necklace is gone! I've had it since I was a baby, and I was just wearing it a little while ago! Why is all of this happening to me?" she wailed, throwing herself onto the ground and burying her face in the skirt of her wet dress.

Jett placed a comforting hand on her shoulder, crouching next to her and saying, "Maybe it came off in the lake. Would you like me to look for it?"

Prissy raised her head, looking at him through her sudden tears and sniffling slightly. "That—that would be wonderful," she said, calming somewhat.

"Then I'll do just that," Jett said with a sweet smile. He picked up his trident again and went over to the lake, using it to explore the water's depths for her lost necklace. It wasn't long before he brought it back to the surface, a glimmering golden chain wrapped around the trident's prongs.

"That's it! That's my necklace," she explained as Jett untangled it from his weapon, looking it over with a serious, troubled expression.

"What's wrong, Jett?" asked Lonnie, walking up and examining it himself. "By Abellio," he swore in sudden amazement. "Is that what I think it is?"

Prissy was extremely confused. "What do you mean? It's just my necklace. Give it back," she insisted, striding over to grab it.

Jett held it out of her reach, kindly explaining to her, "Your necklace is enchanted. Only a wizard could have made something this powerful."

"What? It used to belong to my father, but he died before I was born. I've had it ever since I was a baby." Prissy succumbed to tears again, feeling completely worn out and just wanting to go home. "Please give it to me," she cried.

"Okay, you can have it back," Jett said, handing it to her. Prissy's hand closed around the delicate chain in exhausted gratitude, fastening it around her neck and adjusting the charm to be in the center.

The other two didn't react very well. "Jett!" they both said in accusatory voices.

"What? It belongs to her," Jett explained timidly. "Who are we to take it away?"

The girl put her hands on her hips. "It's an enchanted object! It's our duty as Demonslayers to confiscate it and report it to the Court."

Lonnie nodded. "I agree with Tansy. It isn't safe to leave something like that with a normie."

Jett looked at Prissy again, but there was now a clear message in his eyes: Get out of here. His gaze subtly flicked to his left, indicating that Prissy should leave in that direction. She shot him a brief, thankful look, and took off running as fast as she could back towards the festival before the others could stop her, her wet dress slapping against her legs with every step.

It turned out that Prissy made it back to the renaissance faire just in time for the joust. When she caught up with Ezra, hyperventilating from her run and still soaking wet, he gave her an understandably confused look.

"Did you go swimming to make your costume more realistic, or what?" he asked. "You seriously look like drowned Ophelia now."

"Um… yes," she explained lamely as they entered the jousting arena and found their seats. Along the way, several people looked at her as if she had sprouted a pair of wings, but she was too out-of-it to care for once.

"Well, it's too bad that you didn't think of that before the costume contest."

The costume contest… It seemed as if it had happened weeks ago. Prissy wrung out her hair, lake water splashing onto the wooden floor beneath their row of bleachers. If she hadn't been soaking wet, she would have assumed that everything had been a bizarre daydream.

Her hand found the charm of her necklace again, finger tracing the interconnected lines of the Celtic knot design. Is it really an enchanted object? she mused to herself, all of the strangers' words echoing around in her head and bouncing off one another like lethargic bees.

But then, the joust began, and Prissy welcomed it as a distraction from her confusing thoughts.

Author's Note: Please leave me a review. Much appreciated!