Disclaimer: I don't own any of the iterations of Sherlock Holmes that exist in the world, but in particular no the BBC's Sherlock, nor do I own Buffy the Vampire Slayer.

Sherlock had been both pleased and displeased simultaneously when he discovered the number of supernatural cases he had dismissed as mad. Pleased because many of them were still investigable, and the novelty alone meant that he was enjoying even the easy ones. He was displeased by the number of cases he had missed or that could no longer be investigated, and equally displeased that the reason they had been coming to him was that they believed him to be a spellcaster of some nature, rather than because of his skills in deduction and observation.

When he had expressed his irritation to John and Summers they had both expressed sympathy, John suggesting that he inform them of the truth, and if they didn't believe him but it affected the Work, remind them that he had told them he was not a spellcaster. Summers had said that she usually let people believe her deductions were some sort of psychic power, mostly because they seemed to believe that she ought to have it. "And I have something," she said. "But looking at it logically is usually less . . . fluffy."

"Fluffy?" he inquired. Her terminology was sometimes less than exact, but usually –

"Oh, I-know-there's-a-thing-thereish," she said, gesturing vaguely. "Rather than, I-know-that-specific-guy-is-a-vampire," she continued, pointing at a middle-aged man in a suit that was ten years out of date.

– Exactly as it was the other times she had been vague in that way. The concept was a suitably vague one that did not adapt well to concision.

However, the pointing begged the question, "So, that man is a vampire?"

"Absitively," she said. "Pallor's usually a good secondary indicator, but I find clothes can be a dead giveaway." She smiled as she took in his attentiveness. Based on her appreciative look, she was enjoying an apparently novel sensation of someone listening to her deductions. She was not unused to others listening to her orders or the discussion of things either a slayer or 'valley girl' ought to know, but it was seemingly rare for others to listen to her in other quarters. "The thing is, you can see his supposed age, right? The kind of monetary success you'd expect based on the quality of the suit, etc. etc."

He smiled as he saw where her train of thought went. "But someone who is of that age, and able to afford that suit, would not be wearing that suit. Or rather, would not choose to purchase one of that appearance."

"As I once said to Giles, only someone living underground for ten years would think that was still the look," she said, smirking. "They can't see themselves in mirrors and a majority go underground to the sewers."

"His shoes," Sherlock said, having long since noted the filth around the bottoms.

"Exactly. So, he's not able to see the new looks, and like a lot of older people gets stuck on what was the look in his day. Now, he's probably only about a decade in as a vampire, which means he hasn't yet learned about how to look timeless, assuming he'd ever learn to-"

Her acerbic observation made him laugh, interrupting her. She smiled back and continued. "There's also inappropriate clothing for the weather, because vampires don't suffer from heat or cold the way we do, they're just aware that it's colder or warmer unless you're talking arctic or volcanic sorts of extremes."

A good point to note. Sherlock nodded.

"As always, of course, you have to consider the whole context, but I'm sure you know that," Buffy said with a careless and much-appreciated assumption. "But if you're uncertain, just look for a reflective surface." She promptly pulled out a makeup mirror, turning her back on the vampire and checking and altering her makeup in a most ostentatious fashion.

In a moment she had transformed into a younger-looking woman, closer to teenager than her thirties, both attractive and apparently avaricious. The supposed appearance of greed was borne out when she approached the business-vampire, saying witless things about 'sugar daddies'. It was a command performance and Sherlock followed them out of the pub they had met at for his introduction to the world of trolling for vampires. The vampire's face shifted into its demonic mien just as he arrived, and they fought, briefly. The vampire was clearly outclassed and Summers killed him with remarkable rapidity. She was brushing the vampire ash off her clothes as he approached. "A pleasure to watch," he informed her.

"Thanks," she replied cheerfully. "I try hard not to miss the days when I bantered with them, because when they banter it usually means they're smart enough to be trouble. But it's fun," she complained.

The complaint had a familiar ring to him. "I believe John would say that it's a bit not good," he commented. "He was very unhappy when I enjoyed facing off with Moriarty."

"He doesn't get to say stuff about it, not when I caught him punning at that vampire in the rugby uniform the second time I took him out with me." She shot him a coy look. "Not that it was that good a pun, but the principle stands."

Sherlock felt a smile tugging at his lips. John's ability to find humour in macabre or unusual situations was one of the characteristics that made them so well-matched as friends. Summers' self-reported tendency to make bon-mots in the midst of a fight would be of a similar nature. "John also informs me that it is not done to laugh at crime scenes."

"Depends on the scene," she told him, "but he needs to think about that sort of thing if he's going to tell us off."

He realised then he was leaning in more closely than was normally socially acceptable, and stepped back. A microexpression of . . . disappointment? . . . flickered over her face before smoothing back into her previous facial expression. "Perhaps we might continue my introduction to your domain?" the detective inquired.

"Of course," she said, and led him out onto the street. The evening was interesting and informative, and despite Summers' ridiculous habit of girlish posturing for effect and the painful colloquialisms and Americanisms that peppered her speech, she was an entertaining interlocutor. Most delightful was how little explaining he had to do as he spoke, as she seemed to catch most of his ordinary deductions, allowing the conversation to skip that painfully necessary step of deduction he required with everyone else.

When she was forced to act as a civilised adult and introduced herself by her middle name of 'Anne', he was delighted. "So, you do have a not-thoroughly-ridiculous name," he said.

"You're going to start calling me Anne, aren't you?" she asked, sounding a little wry. "Just keep in mind no one will know who you're talking about."

Sherlock waved off that concern. "I already spend far too much time explaining myself, your name will not add significantly to the burden."

They parted at the end of the evening, plans made for another trip to show him more parts of Anne's underworld. Several weeks later, he knew his affection for her had deepened irreparably after they had both cancelled their meetings several times each for their respective Work. He had felt no need to call her for his cases, as she had not called him for hers, and the smile that lit up her face at his lack of care for her 'ditching' him made his feel things that were all sorts of vile cliche. The way that she had also only wished for him to spare a moment to text her that he was not coming because he had a case on, so different from anyone else with whom he had attempted a close relationship in the past, increased those cliched 'butterflies'.

It was so easy to fall into conversation, so delightful to watch her deduce things in her own sphere, and Sherlock realised he might be in a bit of trouble, so to speak.

It was a few months after Sherlock's return that John finally managed to get Francesca out on a date. It was three dates later that he realised why he was so tense during those dates.

"If you're that concerned about Sherlock," Francesca told him, "Then just call him."

"No," John said decisively. "He . . ." he trailed off as he realised that his tension came from waiting for Sherlock to call with a crisis, or even just to demand John's attention, and not getting the call. "He hasn't been calling," he said, in some wonderment. He sighed. "I'll just have to ask him about it when I get home, and trust that he'll call if he needs me."

It was an act of will to focus on Francesca, but he didn't feel any niggling concerns from the wards around their flat, Sherlock didn't have anything on, and he had to trust Sherlock to act like an adult. If he didn't he was no better than Mycroft. And he did want to be better than Mycroft in some way. With those thoughts in mind, he enjoyed his evening, and went home with his girlfriend.

"I trust your evening was pleasant?" Sherlock inquired as John walked in late the next morning.

John eyed him, but decided to take what Sherlock was saying at more or less face value. He'd find out soon enough if his friend was being sardonic. "Very," he replied, smiling. "If you'll excuse me, I'll change into fresh clothing."

Sherlock gestured in that vague of-course-just-do-it-John way he had, turning his focus back to whatever noisesome experiment he was working on. When he came back downstairs, he asked John a few questions about field surgery and creative uses for things not normally meant to be used in surgery, that came up when one was in an under-supplied hospital.

"That was most helpful," the detective told John. "What is it you are thinking of asking? You have been looking at me repeatedly, and several times shook your head as though to dismiss a question."

John had become used to that before Sherlock's fake suicide, and was happy to have become used to it again. "Mostly I'm trying to figure out how to put this without it sounding like either an invitation, or an attempt at making you feel guilty." He kept on talking before Sherlock could say something that would throw him off, or make him lose his nerve. "Before, when I went on dates you'd call me during them. You'd have cases, you'd have set the flat on fire-"

"That was only the once," Sherlock promptly objected.

"You called to let me know you thought you might have got yourself infected with a particularly virulent and deadly strain of 'flu and would I come and help you prepare for the fallout," John responded. "The point, Sherlock, was that you wouldn't let me get through a date without interrupting. Usually you only left me alone after I'd had an argument with you, and then I spent the whole time tense about what you were getting up to."

"I fail to see how your inability to maintain focus was my fault on those," Sherlock replied.

Sometimes it was impossible to know if he was being deliberately obtuse or simply couldn't understand implicit points. "It's neither here nor there," John said, "But I'm establishing the previous state of affairs, because these last three dates I've been on with Francesca have been different. You not only didn't interrupt, you also didn't say awful things about her or to her, and I haven't been called away on a case." Looking around, John could see the telltale signs Sherlock had begun investigating something. "In fact, you seem to be in the middle of something and you didn't call. Why not? And I mean why not regarding all three dates, not just this most recent one."

"I don't want you to leave," Sherlock admitted. "I . . . Francesca has made you happy, happier than any of the other women you dated before. I worry that if I press too far that you will leave. But more, your happiness is . . . it is paramount."

The words seemed to have been torn from his friend. "Let's talk about this, then," John said. "This one time, and then we'll never have to do it again, and you can pretend you have no emotions and I can pretend that we're not acting like big wibbly sooks." He braved the moment. "This platonic soulmate thing, it means something, all right? It means I love you, like a brother. I don't want to kiss you or whisper sweet nothings in your ear, but you are . . . essential, I suppose. I won't be happy without you. So you don't have to worry I'll leave." Then he hastily added, "But I still like dating and sex and women, and I'd probably be happier if I had the chance at that."

Sherlock took it all in, his eyes intense. For a moment there was silence, his gaze flickering up and down, taking in everything John was saying, his stance, probably something about John's hair follicles, and suddenly he relaxed. "I can still call upon you when you are on dates?"

"If it's actually important and not just that you want me to hand you something sitting on the table behind you," John replied.

"Understood," Sherlock said. And they left it at that. The next date went uninterrupted, but the one after that he called John because he wanted John there for a stakeout. Francesca was understanding, and John was hopeful that perhaps they would get through it.

It was much later that John discovered that half the reason for Sherlock not constantly interrupting was that Sherlock had a new distraction. He arrived at 221B late one morning only to run into Buffy as she was heading out the door, a suspicious bruise on her neck. "I suppose that slayer healing will clear up that love bite?" he asked.

She smiled, looking embarrassed. "I guess I should have said something, but I really didn't want to deal with any 'other woman' jokes, what with him being married to his work and all."

Sherlock's voice spoke from the top of the stairs. "I fail to see how one metaphor I never informed you of should have any bearing on our interactions."

"You do realise I talk to other people, like John, who tell me things?" she asked, with an affectionate smile.

"But your Work is clearly as important as mine," Sherlock said, "So it is hardly as though you cannot understand the prevalence of its place."

The smile on Buffy's face dropped away. "Maybe, but someone constantly ragging on you can get kind of annoying, and I'm pretty sure one or both of us would've heard it from John."

John was about to be offended at the assumption he would tease to that extent when Sherlock spoke. "What is it that is truly upsetting you?" he asked her. "I cannot believe you to be so sensitive to such things."

The doctor looked over at Buffy, who said, "It's . . . nevermind." She waved a hand at Sherlock, trying to dismiss the issue.

Eyes narrowed, Sherlock replied, "I do mind." He strode down the steps, whirled and placed himself between Buffy and the door. John glanced between them, suddenly trapped, because whatever argument they were about to have, he was about to be in the middle of it, with no way to quietly sneak off.

"Look," Buffy said, "It's not a big deal, and-"

"Then you will not mind elucidating why my statement about your understanding of the importance of the Work has you overset."

She eyed him, "I'm not upset," she said, then clearly tried to change the subject. "Anyhow, we were on the topic of John being nice enough not to bug people about things like you being 'married' to your job."

John didn't realise what she'd said, but Sherlock caught it. "My 'job'?" he asked. "I had assumed with your 'Work'-"

"It's a mystical calling," Buffy snapped. "It's not work, it's not something I chose, it's something that's been woven into me by magic and assholes in a desert casting spells to bind powers they didn't understand. You can choose not to solve crimes and take up professional violin. You can choose a lot of things. I can't."

Sherlock reared back. "I see. Because I didn't have some mystically inclined guide appear to inform me I have no choices in my life, what I do is unimportant."

"Of course it's important, but it's not the same," Buffy said. She closed her eyes, clearly trying to rein in her temper. "Look, what you do is important. It's important because it helps people and it's important because it keeps you from going crazy from boredom. It's just . . . if you had different interests you'd be doing something else to do those same things. I didn't get to decide based on interest, I got to decide based on the universe making me the only choice to stop horrible stuff from happening."

John saw it before it happened. He knew Sherlock and knew that when his friend was hurt he could get vicious. The detective didn't hold back. "I should have known better than to expect someone who would play with people like Mycroft would understand."

Buffy staggered back a step. That was Sherlock for you, finding a point of vulnerability and exploiting it. He didn't bother with that sort of thing unless he had a specific outcome in mind, but this time he clearly wanted to hurt the blonde the way he'd been hurt by her apparently dismissive opinion about his Work. Buffy, in response, fled past Sherlock with inhuman speed and agility.

After the door slammed behind her, Sherlock turned to John, practically daring his friend to take her side. "I'll talk to her," John told him.

"And explain what?" demanded the detective.

"That she can't take her anger at her other friends out on you," John told him calmly. It was one thing he'd learnt with Sherlock very soon after they met. The younger man was so very used to the immediate criticism engendered by his inability to stick to polite social mores that he assumed (most of the time not wrongly) that people would side against him. "She was in the wrong to react that way, particularly since you in no way had belittled her Calling. You took the conversation off-topic, but based on things she's told me about her friends and things I've heard from her friends, she's been asked more than once whether she's tried not being the Slayer."

Sherlock's eyes closed in sudden understanding, recontextualising some previous interactions. "An emotional reaction to an unintended reminder, which she had tried to suppress." He looked chagrined. "It did not occur to me that her concerns were unrelated to our conversation. She is usually quite skilled at maintaining a logical perspective on matters."

John shrugged. "Buffy's a lot more openly emotional than you are," he said. "That's not really news. You'll just have to remember the sorts of things you choose not to say to Mrs. Hudson or me that might be hurtful."

They were interrupted by a text message from Lestrade and the next several days were spent investigating a serial killer who seemed to be choosing his victims based on whether they had a particular sort of antique hatstand in the house. John wasn't able to talk to Buffy until the week after, only catching her by chance as he left the little clinic where he'd been doing a surgery on an Indian demon with a species name he couldn't pronounce whose family ran the best curry stand around Southwark. The surgery was simple, their species equivalent of having an appendix out, but there were few trained surgeons who could work in the demon community and John was happy to have the favour of free curry whenever he stopped by in exchange.

Buffy was in the area on her own business and John caught up to her. "Buffy!"

She smiled weakly at him. "Hi, John. what brings you down here?"

"Amandeep needed her muragabi gland out," John said. "I never can thank you and Willow enough for letting me be able to be a surgeon again."

"It's nothing," she said. "Really, you kind of did me a favour in good will by doing this, because everyone knows I introduced you to the community, so they're more likely to trust me."

It was now or never, and John knew that if he let her get the bit in her mouth she'd gallop off. "Can we talk?"

Her eyes closed a moment, whether in tiredness, exasperation or any number of other possible emotions, John didn't know. She still nodded and they headed to a nearby Starbucks. There was something comforting about the impersonal nature and ubiquity of the coffee shops. You were provided an odd sort of privacy by virtue of it being corporate rather than local, no one wanted to impinge on anyone else's conversations. "I'm guessing this is about me and Sherlock," Buffy said. Then she went on the offensive. "He started it. He wouldn't let go and then he compared my calling to his job."

That was Buffy all over. It was in her nature as a Slayer to be combative, and John also suspected it was a habit she'd developed since leaving her friends back in Cleveland, in order to avoid having someone tramp all over her again. But he wasn't going to let her get away with this. "His job? Given that for Sherlock 'The Work' - and I know you know both words are capitalised - is comparable to a priest's calling to God, I think calling it a job is underplaying its importance."

"It's not the same-"

"It's never the same," John interrupted her. "For one thing, I don't believe Sherlock even once compared what you do to regular employment, you did that to him. You denigrated his Work, and I'm fairly sure you even know that you did it because you didn't let yourself tell your friends back in Sunnydale that they were missing the point."

Buffy tried to rally. "Look, we were talking about why Sherlock and I were sneaking, which frankly really was just that I liked the idea of having a boyfriend to myself without having to tell everything to all my friends and he's the one that made it about the slaying."

"You made it about your Calling when you reacted to his comment as though it were a dig at you, rather than Sherlock speaking complimentarily of your ability to understand the higher nature of his own calling." He fixed her with a Look. "Maybe he shouldn't have pushed, but it's a reflexive reaction on your part to assume the person you're talking to sees slaying as something you can quit, like a job at an investment bank."

The Slayer opened her mouth to reply, then closed it, pursing her lips but looking chastened. "God, you're right," she finally said. "Do you think if I apologise he'd accept?"

"Most likely," John told her. "He was going to spend the day sulking that Greg didn't call him in on the latest case before the killer confessed."

Buffy laughed. "I'd be a little put out too if I had something that fun yanked out from under me."

That was unexpected. Buffy liked the challenge, but she didn't tend to call it fun. "Fun?" he asked.

"Sherlock finds it fun. I enjoy killing stuff and letting loose on vampires. Most people really don't get it. I don't quite get how much fun Sherlock has with his cases even though I do kinda enjoy solving them, but it's clear they're fun for him."

John knew then he had to support the two as a couple, because it was so rare to find someone who didn't react with horror to Sherlock's pleasure at a new and interesting puzzle. "Head back to 221 and apologise," he told her. "I really do think he'll forgive you."