When Sherlock had decided she would allow John to move in with her, she had been hesitant. As much as she had wanted to ignore the warnings from Mycroft and dismiss them as unfounded, Sherlock knew in the back of her mind that Mycroft was more similar to her than she was willing to admit. However, 3 months had passed since John had moved in and she had never looked back. That was, until one Friday evening.

John had come home, tired from work and looking for a peaceful moment. Sherlock, who hadn't had a case since the weekend before, was full of angst. Several experiments were running at the same time, including one that looked as though it would explode at any moment, and as John walked into the kitchen to put the kettle on he noticed her long black hair flowing dangerously near to the open reaction.

'You're tired.' It wasn't a question. Sherlock was merely observing and pointing out the obvious. Anyone could have told John that but it was okay. It showed a glimmer of caring behind the cold eyes.

'Excellent deduction. One of your finest really. Next to "you have a penis" and "your hair is blonde."' He couldn't help the sarcasm, even if she did mean well.

'Oh please, you know I didn't mean it in that way.' She still hadn't looked up from her chemistry as he bustled around the kitchen trying to find a spare teacup, swearing when the kettle clicked off and he banged his head on the cupboards above the counter. 'I was merely observing that you will probably want to sit down this evening instead of discussing potential serial killers with me.'

'That would be… good.' Sherlock was learning to read John better even if John still couldn't wrap his head around her. She was just so… Sherlock. Unlike any woman he had met before. She could happily flounce around the flat in next to nothing and then appear in a flash, fully dressed, if Lestrade texted and needed her assistance. He couldn't wrap his head around this mystery.

Sherlock, on the other hand, almost had John sussed out, for the most part. He was your average man in most respects. She had known this from the start. Of normal intelligence, nothing brilliant, but certainly not stupid, he had normal feelings for women, and she even noticed him staring at her sometimes. She didn't mind. Not really. It was to be expected, of course, if she was going to run around the house in her underwear.

There was one thing, however, that she still could not understand. Despite his obvious interest in her, he had never done anything to act on his feelings. He knew, obviously, that she wasn't involved with anyone. This much she had made clear from the start, although she had been vague about how much she was willing to get involved with someone. But none of this really mattered. It was all semantics for something that ultimately Sherlock refused to try to understand: sexual love.

John sat down in his armchair reading one of the latest mysteries that had come out. Sherlock had scoffed at him for reading such drivel, but had left him to it. Whatever the book was seemed to interest him enough that she didn't question him again. He was just starting to get to a thrilling bit when Sherlock, mostly naked, came and sat down on the armchair across from him, legs crossed. She had obviously taken some clothes off, as working with chemicals brought out some of her sensible nature and she had been fully dressed 15 minutes previously.

'What's occupying you?' This time it was a question. John was secretly pleased she hadn't figured out everything on his mind for once.

'What do you mean? I've had a long day at work, I just want some quiet.'

'Oh please. You've had a perfectly average day for your work at the clinic. Someone came in with an ear problem, you gave three flu vaccines to three perfectly normal older ladies, after lunch a boy came in with a broken arm, you've drank three cups of tea since you were at work and your final patient thought she had a tumour on her left breast which simply turned out to be swelling from her menstrual cycle. Sounds pretty normal to me.'

John looked stunned and put down his book. Now she was just showing off to get his attention. It had worked. 'Do you really want to know?'

'Yes. I can't figure it out and that's bothering me. It seems like woman problems, but it can't be. You haven't been on a date for a month and a half and there don't seem to be any women in your life you even want to go out on a date with.'

John hesitated. Sherlock wasn't one for typically talking about feelings so it was probably to his advantage to express himself before his frustration became too much. 'It's you, Sherlock. You're the preoccupation.'

'I thought I was doing better with the experiments! I haven't done anything quite so extreme since the eyeballs in the microwave!'

'It's not that. It's… How do I put this… lightly? You, you-'

'Please spit it out. I can take bluntness, as you know.'

'I haven't been on a date in almost two months because of you.'

'I haven't been stopping you, have I? Surely the women in your life understand how unappealing I am to you.'

'Except that it's quite the opposite.'

Now Sherlock was beginning to understand Mycroft's warnings. He had called her, late one evening when she was busy and wanted to text. She was irritated and barely listened to him, although the words still rang in her head: 'You know he'll just end up like all the others: smitten although he won't realise how it happened and unable to turn back. Get out of it while you can. Caring is not an advantage, Sherlock.' He had spoken to her as if they were the same person, simply saying exactly what he would do if presented with a flatmate of the opposite sex. She wasn't sure what was right.

'I don't know what to say.' She honestly didn't. Men had been interested before, it was true, but she had felt revulsion when they had begged her to go on one date… 'It'll change you, I promise! I'm the one.' But this time? She wasn't sure… John was different.

She wasn't really sure why he was different. He did the same things as the others: staring at her when she walked around barely clothed, asked her about her love life and evidently got himself off a few times a week. But for some reason in John's case, words spoke louder than his typical male actions: he never complained that she was 'such a tease for walking around the flat that way,' he eventually stopped interrogating her about her lack of love life and he even apologised to her after he had made some particularly loud noises one evening that carried throughout the flat. Most of the men she had lived with just gave her a knowing smirk, as if inviting her to join them.

'What do you mean, you "don't know", Sherlock? Surely this is a yes or no question.'

'You never asked a question.'

'Well I think I just made myself clear about how I feel. And I suppose you have as well, numerous times in the past. You're 'married to the work'. I don't know why I even brought this up with you.'

He was getting ready to haul himself out of his chair when Sherlock rapidly blurted out: 'I meant what I said. I honestly don't know what to say.'

'Care to explain yourself?'

'You aren't like the other men I've lived with. I mean, you are. You do the same things, in principle. That's why it's difficult for me to look past them. But, at the same time, you are completely abnormal. You somehow seem to understand, even if you have difficulty controlling your average male urges.'

'Yes, well, I do happen to be a thirty-something man.'

'Will you allow me to think on what you've said?'

'Certainly.'

'But John,' she interrupted him as he was moving to get up again, 'no matter what this turns into, I'm still not normal by any stretch of your imagination. I'm… asexual.' She paused for a moment, contemplating her words and then spat some more out quickly: 'If you don't know what that is, look it up.' With a swish of her hair she was back in the kitchen, attempting to make something explode again.

John couldn't go back to reading his book after what Sherlock had said to him. He wasn't even sure what it meant… that word, 'asexual.' From what he knew, he knew he didn't really know a thing. So many negative connotations were floating around his head, and yet this was Sherlock. It could never be so simple as a woman who couldn't get any sex so she says she isn't interested in it. He grabbed his laptop and went into his room upstairs, not eager for Sherlock to invade in what he was looking up. She would have a smug grin about his cluelessness.

John stumbled across a site called AVEN after a quick search on Google. It seemed decidedly helpful and he began to read more and more. Definitions were swirling around in his tired brain and sometime between 9:30 and 10:00 he must have fallen asleep with the light on and his laptop open.

He heard a decided knock on the closed door. Waking up with a start he looked at his watch. 10:42. John closed the now black laptop screen and called to let Sherlock in.

'I've been thinking.' She came in, fully dressed this time, not even taking the common courtesy of asking if she could sit on the bed with him.

'Yes, well?'

'Have you been as well? Because this isn't a one-sided issue, you know.'

'I have… done some research and made deductions, as you would do.'

'What have you deduced about me, then? That I'm a freak? You think I can be cured by you giving me mind-blowing orgasms and I'll suddenly want you like those women you meet sometimes?'

'Nothing close to that, actually. While you are an asexual, you did not say that you were aromantic, which to me would indicate that given the right person you are more than willing to participate in a mutually-enjoyable romantic relationship. You did not specify your romantic orientation, but I can at least assume that you do have some feelings for men, or we wouldn't be sitting her right now, wondering where our friendship is going. How am I doing?'

'Impressive, Doctor Watson. No one has gotten this far before. Please, continue on your deductions.'

'Well, there are still many variables involved in this potential relationship. You would need to express your boundaries to me, because for some asexuals kissing would be considered a sexual action, while for others it is simply showing affection. I, of course, will respect your boundaries, but they would need to be discussed. There is also the issue of my being attracted to women sexually. This, unfortunately for you, includes you, Sherlock. A few aces in the forums I read said they were comfortable with their other half getting sexual pleasure outside of the relationship; however, I don't feel comfortable with this. We would have to come to some sort of compromise.' Sherlock looked up from her dream-like state with a start, as if that had triggered something. John realised this and took back his words. 'I do not mean some sort of sexual compromise. Please. I know enough about boundaries to know that intercourse is not an answer for us, at least, unless you say it is. Which is completely your choice and I will not pressure you.' He said the last words incredibly quickly, as if to stop any assumptions before they became churning thoughts in Sherlock's brain. 'It is simply something to discuss.'

'You're spot-on in almost everything, John. You really are. Thank you. We can certainly discuss these urges at another point.' She sat there, silent and completely still.

John waited a few awkward minutes and interrupted her silence. 'You don't have anything to say?' He had just expressed that it truly was 'all fine', but he needed some sort of indicator from her. Even Sherlock must surely be capable of some sort of expression of feelings.

'From all your reading you must surely understand my dilemma then. As much as I do think you are different and I can see us starting a life together as more than friends, there is always this fear that you'll leave not because affection has waned, but because I cannot provide you sexually what you desire. I am not entirely clear to myself what my boundaries are. It's been a while since I was in a relationship with someone, and they certainly didn't respect how far I was willing to go when I had no sexual attraction to them.'

'Can I be blunt with you, Sherlock?'

'Please. It's easier than beating around the bush.'

'Do you have a libido?'

'Oh. Well, I suppose that I do. However, I suppress it for most of the time. It's easier that way. It doesn't get in the way of the work.'

'Please don't assume I asked that to con you into having sex with me.'

'No. You're just curious, it's understandable. You've done your research well. You really have.' John was smiling. Sherlock was never this kind to anyone. This man was clearly different, even if he didn't realise it. 'Let me think about all this. Can we discuss over tea tomorrow morning?'

'Certainly.'