"Jem..."

"Will, I'm quite alright."

The darkened streets of London, lined with houses and shop fronts, had retired into silence. Only the streetlamps, burning steadily with gaslights, lit the colourless sky. Against the clouded horizon, the church steeples and roofs looked black, thrown into silhouette, the full moon edging hesitantly out from between the thick smog clouds that permanently hung low over the city. London was so rarely silent, so rarely still. In daytime, the smoke from the chimneys, the creaking of carriage wheels and the bustle of thousands of mundanes made the city ugly. Perhaps not ugly, exactly, but less becoming. It was preferable like this; held captive in quietude, in elegant twilight.

The streets were bare on the surface, at first glance. Upon closer inspection, the pavements were crawling, heaving with life, with all kinds of people. In doorways, prostitutes sat, dresses tucked up, revealing pale legs covered by hole-dotted stockings. On the banks of the murky river Thames, mudlarks sifted through the accumulated rubbish for items of value. And deeper, in a narrow backalley behind a row of abandoned buildings, walked shadowhunters William Carstairs and his parabatai James Carstairs.

"Jem, do you really think this is sensible?"

Jem turned to Will, looking amused.

"You are lecturing me on sense?" Jem laughed. "How novel."

Will grinned. "Well, I suppose I just possess a wisdom beyond my years."

"Perhaps if you were five."

Will allowed the topic of whether their being out so late was wise to drop, not wishing to upset his parabatai. But, though he failed to show it often, Will was becoming increasingly concerned about his friend. Jem was unwell. Will had known that for years, since the moment he had met him. Since that first ever day together, Will had known how this tale would end; with Will's parabatai rune fading to nothingness and Jem's name on a tomb in the Silent City. He knew that, already, Jem had had a life far longer than anyone could've ever imagined. Jem believed he had been lucky, but Will disagreed – privately, of course. Sixteen years was not lucky, even in the eyes of a shadowhunter who was at risk of life-threatening situations daily. Jem was not fortunate. Not at all.

As if proving this point, Jem shivered violently, clenching his teeth to stop them from chattering. He pulled his thick winter coat tightly about his shoulders, leaning heavily against his cane. His knuckles seemed about to tear through his pale, paper-thin skin. It was the height of summer, but Jem shook in his winter clothes as if it were December. Will allowed his mind to blame this on the fact it was night and the sun had set hours ago, casting a cool edge to the darkness that Will personally found pleasantly temperate. He walked a little slower to allow his companion to catch his wheezing breath. They had walked too far, Will thought. Jem would be exhausted and cold, and Will desperately wanted his friend in as good health as possible.

The moon appeared from behind its wall of cloud, casting the two boys into a pool of moonlight. Under this illumination, Will looked radiant. His skin glowed and his blue eyes shone, dark and unpredictable as a thunderous sea. The other boy, however, was forged in silver. His hair and eyes glinted like a shilling, and even his skin had a light grey-ish metallic sheen. The Yin Fen, the very drug that was keeping him alive, was sucking the life from him, silently and slowly murdering him. The drug had taken Will's parabatai, with dark eyes and black hair and wicked wit cloaked in innocence, and replaced with frozen silver.

From the mouth of the dead-ended backalley, a sharp intake of breath came.

"We have company, my lord." A deep voice purred.

Will and Jem exchanged a glance and both nodded in silent understanding. Jem swung his cane up, clicking the side and releasing the razor-sharp sword tip from the end. Will yanked a blade from his belt, holding it aloft. The seraph blade sprung to life, lighting under Will's touch and illuminating the alley somewhat.

"Who goes there?" a voice called from the darkness. A child's voice, with the diction of someone brought up in wealth. "I say, who goes there?"

Will and Jem stayed silent. This was a child talking, but a demon could easily take on a voice. However, what was odd was that this person had called out to them, not the other way around. Interesting, Will thought.

"I demand you reveal yourself!" the voice commanded.

"Will Herondale," Will called back. "And Jem Carstairs."

From the darkness stepped a small boy unusual enough to make Will suspicious. He was well-dressed, a cloak wrapped around him. But despite his youth, like Jem, he clutched a cane. His eyes were very blue; or Will thought, his eye at least. The other was covered by an eyepatch and his black fringe hung low across his forehead.

"Earl Ciel Phantomhive," he said. "And my butler, Sebastian."

A most unusual man stepped into the pool of moonlight beside his master. He was taller than any man Will had ever seen, and odd in appearance. He swept into a low bow, his coat tails fluttering in the wind. His hair was quite too long, the back of his black locks brushing his collar and long strands about his face. But it was neither his immense height nor his unusual haircut which unnerved Will. No, it was his eyes. In the dark, Will was not certain, but they looked almost red. Will shook this thought off, telling himself he was being foolish, it was merely a trick of the light. Nevertheless...

"Gentlemen," Sebastian said, and Jem and Will inclined their heads in response. He turned to Ciel. "My lord, we had better move along. It is growing late. I believe we should retire for tonight and return home."

"Very well." Ciel replied, eyes still scanning the two shadowhunters. "Good evening." He told them, and the two strangers turned to go, Will's eyes watching them leave.

But just then, a distinctive smell not unlike the Thames on a hot day filled the alley, making Jem cough. Demons. The backs of the two retreating figures faced the two boys and Jem darted forward.

"Stop!" he cried, grabbing Ciel and yanking him backwards.

"Let go of me!" Ciel shouted. "Sebastian!"

But the butler pushed his master back with an arm firmly and took Ciel's cane from his hand.

"One moment, young master." He said, and Ciel sighed, sitting himself on a crate towards the end of the alley.

"Hurry up, Sebastian. I want to go home."

"Of course." He replied, and swung the cane into his hands with ease.

Suddenly, the mouth of the alley filled with stroke that stung Will's nose and throat. A demon loomed from the smoke, pouring the putrid gas from its gaping mouth, spines on its back and spider-like legs prickling. Will swung forward, Jem beside him, and was enveloped in a vast cloud of the burning fog. Jem lunged into its depth and as he darted his cane towards the centre, it made contact with something and the demon screeched as the sword-cane found its leathery hide. In fury, the demon released a wave of stinging smoke and Jem choked. Will could hear his frienc coughing and knew nothing good ever came of his coughing fits. But Will couldn't see Jem for the dense fog. He groped in the fog and grabbed something.

"Jem?"

"Yes." He wheezed.

Will pulled and yanked Jem back, clutching his arm tightly. They emerged from the smoke cloud that had now overtaken the majority of the alley and sat Jem on one of the crates by Ciel. He watched helplessly as Jem clutched his hankerchief to his mouth, his breath rattling between coughs. He spluttered breathlessly and blood stained the white square of cloth. Ciel looked startled.

"Is he alright?" he asked Will, who nodded wordlessly.

There was nothing Will could do to help, so he turned to Ciel.

"I have to fight that demon with your butler. Please sit with Jem and keep an eye on him. Tell me if anything happens."

"I-I couldn't. I'd..." Ciel began and Will called over his shoulder.

"I'm quite certain he won't die in your arms. That's far too dramatic for Jem. Just make sure he doesn't collapse."

Then he flung himself back into the demon's cloud of smoke and disappeared, ignoring Ciel's cried of protest.

Will returned to the battle with a heavy heart. Poor Jem. But there was little that could be done there and then, so Will flung himself into the fighting, determined to dispose of the demon and return home as quickly as possible. Deep in the unpleasant mist that burned Will's eyes, throat and nose, two red eyes glimmered. The demon, Will thought. But as the figure moved, tailcoat waving like a flag, Will understood. Sebastian. And Will hadn't been mistaken; the man's eyes were as red as blood.

"You have to leave! It isn't safe here!" Will choked, though tendrils of smoke drove themselves further down his throat with each word.

Sebastian wasn't even flinching in the smoke, and when he spoke his voice was clear as ever, unaffected by the fog.

"I believe my assistance may prove helpful."

He swung Ciel's cane over his head and struck down. It connected with the demon, and Will used this to gauge where the monster was. He drove his blade forward and it sunk into the demon's skin before the thing wailed and retreated to its home dimension, the smoke dissipating with its exit.

Will sheathed his ichor-slicked blade and hurried over to his parabatai. Before he even had time to open his mouth, Jem spoke instead.

"William, I'm alright." He said, voice strained with coughing. He clenched his blood-spattered hankerchief tightly.

"We need to get home. Charlotte will be beside herself, more so when she sees your state."

Ciel sat, stunned, and brushed himself off as he stood. Will helped Jem to his feet carefull and Jem brushed off his help gently and tactfully.

"Will, I am not made of glass. I shan't break."

Sebastian presented Ciel with his cane, but the boy looked at it disdainfully, at the ichor covering it.

"Return it to me once it has been cleaned."

"Yes, my lord."

Will turned on Sebastian then. "How in the Angel's name did you fight that demon?"

Sebastian smiled slyly.

"I am simply one hell of a butler." He purred and Ciel flung him an angry look.

"You two must come back with us." Jem said, his breath less wheezing. "Please, we insist. It's the least we can do to offer you a place to stay overnight."

"That won't be necessary." Sebastian said, and bowed low. "Good eve..."

Ciel interrupted him swiftly.

"We shall take you up on that generous offer." He replied. "Sebastian, pull around the carriage."

The butler straightened from his sweeping bow. "Yes, my lord. Very good." Then he spun on his heel and left the alley.

When they arrived at the London Institute, Charlotte Branwell was waiting on the steps. She hurried over as the carriage slowed and helped Jem through the doors and upstairs to his room. The boy had been leaning heavily upon his friend, Will's arms under his seeming to be the only thing keeping him upright.

"Good evening." Charlotte called to Ciel and Sebastian, unfazed by their presence. "Will, please escort our guests to their rooms and see ensure they are comfortable."

Will turned and started walking up the main staircase, breaking into a swift stride and clearly expecting them to follow. They did. At the end of a long corridor, Will pushed a door open roughly.

"Hopefully this is sufficient." He said impatiently.

Ciel nodded. "It is. If my butler might remain with me briefly? We have a few things to discuss."

Will shrugged, uncaring of what they might have to discuss. Perhaps himself and Jem? He didn't care enough to ask. "The room beside this one is unoccupied." He mumbled, and left without another word. He closed the door then broke into a run, racing off to Jem's room to sit with his parabatai whilst he recovered. Perhaps Ciel and Sebastian had a lot to discuss, but so did he and Jem.