"Have you ever been in love? Horrible, isn't it? It makes you so vulnerable. It opens your chest and it opens up your heart and it means that someone can get inside you and mess you up."

- 'The Sandman, Vol 9: The Kindly Ones'

Neil Gaiman

X X X

John was pacing back and forth, back and forth; the length of the room over and over again. His gray eyes were hard, filled with a rash of emotions such as fear, confusion, uncertainty, and disbelief. He was at a complete loss, Sherlock could tell with just a glance. John made it obvious. But, for some reason, John's troubled disposition made Sherlock's throat feel tight and his chest ache in a way he'd never felt before. He wanted to get up and embrace John, to tell him that it was alright, and his mind couldn't cope with that strange desire.

He didn't understand it.

So, he did what he always did, he closed his emotions off to a tiny, abandoned part of his mind and straightened in his chair, regaining his cold, machine-like composure.

"I don't see what's so hard to accept about this, John."

John stopped pacing to throw a glare at the consulting detective. "Well, Sherlock, I'm sorry if my lesser intellect doesn't permit me to accept all of this as easily as you have. I just found out that aliens and demons and angels and a whole load of other rubbish are real for fuck's sake!"

Sherlock raised an eyebrow at the vulgar language John used. But at the same time he heard the tone in John's voice. John was upset, but not just over everything that had happened in the past few hours. It was as if the fact that Sherlock had accepted it so easily had confused him to the point of anger.

Sherlock instantly regretted how cold he'd been early.

"John," the consulting detective began, wanting to somehow apologize, but not knowing the words to use.

"Seriously, Sherlock, just shut up." John snapped as he resumed his pacing, now intermittently running his fingers through his hair.

Sherlock got the sudden urge to do the same thing to the good doctor's hair, and the strength of the sudden want had his fingers twitching with desire, despite the absurdity of the thought. He wanted to tangle his fingers in John's hair, to caress each flaxen strand, to breathe in John's scent and hold him close . . .

With a great amount of struggling, Sherlock shook the strange notion away, shifting uncomfortably in his chair. What was with these sudden compulsive urges he was having all of a sudden? They were new to him; alien. He could never remember feeling anything like this ever before, and it made him feel exposed and raw, as if had been cut open. He didn't like the feeling, but no matter what he did, he couldn't push it away. It stayed with him even as his gray-green eyes followed John across the room.

A sudden ring of the doorbell made them both jump.

"Mrs. Hudson!" Sherlock called, his frustration making him shout a bit louder than he meant to.

He heard Mrs. Hudson get the door, and a muffled conversation reached his ears. Then familiar footsteps ascended the stairs and Sherlock turned, ready for the person who was coming to meet them.

"Lestrade," Sherlock said just as the Detective Inspector entered the flat. "What is it? What's happened?"

Lestrade sighed, looking troubled. "There's been another one." He murmured, "Another murder, and it's definitely the same culprit as before. The crime scene looks like a slaughterhouse."

Sherlock blinked slowly, steepling his fingers and leaning forward a bit in his chair. Finally, after a few moments of silence, he stood with a flourish and grabbed his coat, glancing back when John didn't follow him.

"John, are you coming?"

John saw the plea in Sherlock's eyes and sighed, nodding as he grabbed his coat, "Alright, fine. Just don't look at me like that."

Lestrade made a face at them. He felt sort of lost in the conversation, but he quickly shrugged the sensation off. Sherlock and John did that weird telepathic conversation thing around him all the time where they sort of just stared at each other unblinkingly, so you'd think that he'd be used to it by now.

Apparently he wasn't.

X X X

"This is where you're staying?" The Doctor glanced around the hotel room quizzically, noting the smell, the cigarette burns on the carpet, and the faded floral wallpaper and he grinned. "Wonderful!"

"I wouldn't go that far." Sam said dryly.

Castiel suddenly paused and stared at them all levelly, his expression unreadable. "I do not think we should stay here."

"What? Why not? We've got all our stuff here." Dean retorted.

"Let me rephrase that," Castiel said, "I don't think we should leave John and Sherlock alone."

The Doctor nodded, suddenly serious again. "I agree. They've been working on this case with Scotland Yard, right? So who's to say that this vampire doesn't go after them?"

"You're right," Sam admitted, "Dean?"

"Oh, fine." Dean grumbled, "Grab your stuff then, Sammy, and let's go."

"I will take you." Castiel said as soon as the two had gotten their things together. He stepped forward to grab their shoulders, and Sam reached out just in time to grab the Doctor's hand. Then they were gone – not a trace left behind.

Nearly twenty miles away the four appeared just around the corner from 221b Baker Street. Dean and Sam, used to Castiel's mode of transportation as they were, didn't react much save for sharing a look that was somewhere between exasperation and acceptance. The Doctor, meanwhile, stumbled a bit on his feet and grinned widely, his eyes twinkling with wonder.

"What was that?" He gasped, "It was amazing! It made my skin tingle and my stomach drop – almost like a rollercoaster! Oho, can I go again?"

The corners of Castiel's mouth twitched, "Maybe later.

"It's a date, then!" The Doctor exclaimed.

Dean scowled at the comment, irritated by the Doctor's interaction with Castiel, and Sam resisted the urge to facepalm. Why was everyone around him so oblivious? It was as if they were slamming their heads into a brick wall repeatedly while chanting the words that marked their unfortunate fate; oblivious, oblivious, oblivious.

Well . . . maybe not the Doctor. Sam wasn't sure why, but he had a feeling that the Doctor knew exactly what was going on. Maybe it had something to do with the mischievous glint in his eyes. Sam had more important things to think about at the moment, however. So, shouldering their possessions they traipsed down the sidewalk and up the steps of 221b Baker Street. Sam knocked on the door, and then they waited.

The door swung open moments later to show an older woman who looked a bit flustered and Sam blinked, a bit confused since he'd been expecting John or maybe even Sherlock to answer.

"Oh – oh my," the woman murmured, "May I help you?"

"Yeah, we're here to see Sherlock." Dean said.

"Oh, yes. Come in, come in." The woman muttered. "Sherlock sure is popular today, isn't he? Go on upstairs, then. I think you just caught them as they were on their way out."

A bit perplexed, the four went up the stairs and into Sherlock and John's flat. The door was open as it always seemed to be, and inside there was an unfamiliar man in a suit and coat ensemble. He looked sort of official, and Dean wondered if he was from Scotland Yard. Behind him, Sherlock and John had donned their coats as if they were, in fact, on their way out. Upon hearing their ascent up the stairs, however, Sherlock turned, his eyes widening as he saw them all there.

"We had a bit of a problem," Castiel said by way of explanation as they entered the flat.

"Sorry for the unexpected visit, but is it alright if we crash here for a while?" Sam asked, wanting to at least try to be polite about the request.

Sherlock raised an eyebrow but, thankfully, didn't ask questions. "It might be a bit crowded . . ."

"We're used to that." Sam and Dean said in unison.

The Doctor grinned.

"Who are these people, Sherlock?" The other guest in the flat, a tall man with brown eyes and salt-and-pepper hair, asked suspiciously.

"They're . . ." Sherlock paused, "Acquaintances of mine."

"I see," the man sighed, sounding resigned, "But I really need you to come with me, Sherlock. If you can just give me anything – anything at all – it will help."

Sherlock nodded, "Fine. John?"

"Coming," John said as they headed out, turning to address Sam and Dean just before he left, "You guys make yourselves at home, alright? We'll explain when we get back."

And then they were gone, and suddenly the flat felt sort of empty and hollow, almost alien without Sherlock and John there. It wasn't right. Sam wondered if John or Sherlock ever felt the same way when they were in the flat alone. Considering the way the two looked at each other, he wouldn't be surprised.

"His name is Lestrade," Castiel said suddenly, "Greg Lestrade. He's a Detective Inspector from Scotland Yard."

"Oh?" The Doctor stared after them, wishing he'd gone along. He'd have liked to see Sherlock's deduction powers in action, after all he'd heard about them. He could still catch up with them, though, couldn't he? He had the TARDIS, after all. That seemed like so much work for such a little thing, though.

A sudden idea hit him.

"Cas?" He turned to the angel, "Oh, sorry, it is alright for me to call you that, yes? I don't want to seem presumptuous."

Castiel nodded. "It's fine."

"Good." The Doctor smiled, "Yes, anyway, remember how you said earlier that you'd show me that wonderful relocation trick of yours again later?"

The angel tilted his head slightly to the side in a manner that must've been the closest he ever came to inquisitive, his eyes bright blue in the light. "I do."

"Well," the Doctor smirked, "It is later."

X X X

This time Sherlock didn't have to say anything; John stayed by the taxi without prompting, preferring that to seeing another gruesome crime scene. He'd seen lots of death in his days back in the army, that was for sure, but it had never been anything as bad as this. And Sherlock understood . . . sort of. Nonetheless, he just let it be, as did John. And that was that.

"It's the same as the last four." Lestrade said with a great sigh, "In fact, it's so perfectly similar I want to rip my hair out at the roots. There's no new evidence at all!"

Sherlock glanced around the crime scene, his eyes narrowed. "It'll be alright, Inspector. You can trust me with this."

Lestrade sighed again, looking resigned. "I sure hope so."

"Oi, Sherlock!"

The consulting detective turned as he heard someone call his name and his eyes widened considerably as he saw that the Doctor-slash-alien and Castiel, the angel of the Lord, stood on the other side of the street. The Doctor was waving at him, grinning insistently, but Castiel was as unresponsive as ever, simply standing there with his hands in his pockets.

Sherlock stared.

. . . What? How did they . . . ?

"Hey, those two were at your flat," Lestrade said unnecessarily. "What are they doing here?"

"I'm not sure." Sherlock admitted. The Doctor was already hard enough to read, but Castiel . . . he was impossible. Sherlock could never deduce anything when it came to the angel. Then again the fact that he was even more non-human than the Doctor probably had something to do with it.

"Hello, Sherlock Holmes." Castiel murmured as the consulting detective approached them. Beside the angel, the Doctor was rocked back on his heels in delight; his eyes shining with a child-like fervor.

"What are you doing here?" Sherlock asked quickly, getting right to the point.

"I'm here to see you." The Doctor said, "Or, more specifically, how you are in action."

Sherlock blinked, "And Castiel?"

"Ah . . . Cas just got me here."

Sherlock didn't really want to ask. He could guess at the meaning behind that rather well, after all. But he still wasn't entirely used to the idea of demons and angels and monsters being real and whatnot.

"I can't get you into the crime scene." Sherlock said, "I'm already pressing my luck by getting John in."

"Well, he's not here now, is he?"

"No, he's holding the cab."

The Doctor's eyes darkened slightly then, almost as if he could sense something Sherlock could not. "I see."

"I can cloak us." Castiel said suddenly.

Sherlock raised an eyebrow.

"I'll make it seem as if we're not here." The angel clarified, "No one will know of our presence, except for you, Sherlock Holmes."

"Oh." Sherlock murmured, unsure what else to say.

"How does that work?" The Doctor wondered.

Without a word, Castiel lifted two fingers to the Doctor's forehead. He flinched automatically in response, but nothing seemed to happen. The Doctor and Castiel both looked the same as before. Had the angel even done anything?

"That was strange." The Doctor said then, "Sort of . . . tingly."

"Dean said it tickles."

"Yes, I'd say it does," replied the Doctor, laughing.

Sherlock frowned, his eyes narrowing as he stared at the two. From the way they spoke it seemed as if Castiel had done something after all, Sherlock just hadn't been able to notice the effects it had. Castiel had said, though, that only he'd be able to know of their presence, right? So then that meant that he could see them and everyone else couldn't.

"You have a sharp mind, Sherlock Holmes." Castiel said.

"So, let's see you in action, then!" The Doctor exclaimed, following Sherlock as he headed back over to Lestrade.

"There isn't much to see," Sherlock admitted. "The crime scene is the same as the others, and I can't tell the Inspector about the . . ." He trailed off, feeling as if he shouldn't finish that sentence aloud.

"About the vampire," Castiel finished. "I can see how that would be . . . hard for him to accept."

"I do believe that's what they call and understatement, Cas." The Doctor commented.

"Yes, well," Sherlock said, attempting to guide the two back on course, "The point is that I can't deduce much else from this scene without revealing what I know – as in, who the culprit really is."

"Still," the Doctor urged as Sherlock reached Lestrade's side, "Do whatever you can."

"I am interested to see you at work as well, Sherlock Holmes." Castiel agreed.

Sherlock sighed.

"Did they leave?" Lestrade wondered, staring at the consulting detective suspiciously.

"Yes, I sent them off."

"Good." Lestrade turned back to glance at the mutilated body in front of him. "So, forensics just got back to us. The body belongs to a man named Charlie Bahr, and he happened to be a librarian – which has nothing to do with the jobs of the other victims, by the way. In fact, they have no connection whatsoever. So please, Sherlock, give me something. Anything."

Sherlock nodded. "I will do my best. I already have six ideas."

"Six?"

Sherlock nodded, glancing at the body. "No, wait. Make that five."

"So what is it this time? Something cryptic and metaphorical like before? Listen, Sherlock, just saying teeth and then being all mysterious about it doesn't give me much."

Sherlock shook his head. "I still stick with my previous analysis, though. Someone or something with very large, very sharp teeth did this; perhaps one of those vampiric enthusiasts."

" . . . Vampiric enthusiasts?" Lestrade looked as if he couldn't believe his ears. Sherlock was right there with him, though. He almost couldn't believe what he was saying.

"Yes, haven't you heard?" Sherlock continued, "There are people who believe they're actually vampires and go around drinking human blood. And I have heard of worse cases where mentally unstable patients have gone past 'devotion' into pure 'obsession' and have turned to murdering people and drinking their blood. That would explain why I keep getting the distinct impression of sharp teeth." He paused, "Though of course, that is only one idea."

Lestrade shuddered. "I almost wish you hadn't told me that."

"Yes, but that's all I can provide for now, Inspector." Sherlock said finally, turning to go.

"Wait, Sherlock –"

"Trust me, Inspector," Sherlock said, glancing over his shoulder to wink at him. "I know what I'm doing."

Lestrade sighed again as he watched him go, shaking his head in disbelief. Sometimes he felt as if he didn't know the consulting detective at all, despite how long they'd been acquainted. And this was one of those times. Strangely, though, as Sherlock walked off, Lestrade could've sworn that he saw the shadows of two others walking by his side, their silhouettes illuminated on the side walk for just a moment as the sun peeked out from behind the clouds.

But then the shadows were gone, and Lestrade was left convincing himself it had just been a trick of the light.