A/N: So, this is my first non-Harry Potter fic. It is obviously my only Sherlock fic, and I have a word of warning: I am not very familiar with the Sherlock Holmes universe, as I have never read any of the books or watched any other adaptations other than the BBC show. I also am beginning this story without having seen the last two episodes of season two. This is very AU. It's not meant to fit in perfectly with any of the episodes in particular or anything like that. It's not a rewrite of a familiar story. It's sort of an offshoot of a dream I had. Please be kind. It's a bit of a half-baked idea. I'll do my best to do the fandom justice!

-C

John was tired. It had been a long day, and Sherlock had been in the morgue most of the day. If John didn't know Sherlock, he would say he was visiting Molly an awful lot, but he knew that they were simply dealing with a particularly large volume of bodies lately. It wasn't that John wasn't disturbed by the fact that crime seemed to have risen so much; it's that he had come to appreciate Sherlock's view that being bothered by things didn't help anyone.

But as John arrived at Baker Street something felt off. Sherlock wasn't home yet, but there was someone where they shouldn't be…

"Mrs. Hudson?"

There was no answer, which made John even more worried. He rushed upstairs to 221B, and he saw a delicate arm draped over the edge of the armchair, the fingernails painted bright yellow. It certainly wasn't Mrs. Hudson.

"Can I help you?" John said slowly, hand on his gun. He'd been with Sherlock long enough to know that the women could be just as dangerous as the men. The figure stood gracefully, turning to face John with a neutral expression.

The first thing he noticed was the very familiar, if petite, silhouette. It was like looking at a young, female version of Sherlock. Not in looks, exactly. She had dark red hair, bright green eyes, and her features were completely different. Still, she wore all black from head to toe, and had a long coat similar to the one Sherlock wore.

"You must be John," she said, her voice not particularly low or high, and obviously attempting to keep as even and dry as Sherlock's tone, but with an underlying tone of excitement she was trying very hard to contain. "I suppose Sherlock won't be in for quite a while."

It wasn't a question. She spoke with confidence, very similar to the air with which Sherlock and Mycroft spoke. He nodded.

"I thought as much," she said lazily. "I have some things I need to take care of. Would you be so kind as to inform him when next you see him that Elizabeth Coppens will be renting 221C? I had wanted to see his face, but one can't have everything in life."

She pulled her coat more tightly around her and her slightly curly hair bounced around her shoulders as she made to move past him, but he couldn't help himself.

"Sorry, who are you?" he asked, the fact that she would be living in their apartment sinking in. She paused, turned, and smiled softly at him.

"Why don't you ask one of the Holmes brothers?"

And with that, she was gone.

John frowned slightly, shook his head a little, and went on about his day. Elizabeth Coppens…. The name didn't ring any bells, but Sherlock and Mycroft didn't talk much about their life outside of the world he lived in. He ran over her appearance in his mind, and he realized that she really did behave a fair amount like Sherlock. Was it possible that they had a sister? She wasn't a Holmes…but she could be married? Or perhaps she was a cousin.

"Sherlock, are you in?"

"Mrs. Hudson?" John called. She appeared around the corner with a sandwich. "Sherlock's not here," he said. "He probably won't be back until quite late. There were several cases Lestrade wanted him to consult on and there was apparently a very large volume of bodies. Did you need something?"

She put down the sandwich in front of him and shook her head slightly.

"No, not anything in particular. There's a young woman who's going to be renting the other room. She seemed to know him, you know, Sherlock. I thought he might want to know she was here, but I suppose he'll find out soon enough."

"Yes, I met her," John said slowly, picking up the turkey sandwich. "I suppose she told you who she is?"

"No, not a thing, dear," Mrs. Hudson said, scurrying around, tidying up things here and there. "She was a pretty girl, I'll say that. No, she gave me her name, paid in cash, and seemed quite a nice sort of girl. I didn't think there was much to ask. She paid in cash, you know."

Yes, paying in cash was often the best way to keep people from asking questions. John thanked Mrs. Hudson for the sandwich, and she made him a quick cup of tea. He puzzled a little while longer about the girl…. Elizabeth Coppens…. But there were no conclusions that seemed to come to mind, so John turned to his blog for a while, covering some of their more recent cases and wondering about the girl. When Mrs. Hudson came around a while later to collect his cup, he said, "Mrs. Hudson, I thought 221C wasn't in very good shape? Miss Coppens wanted to rent it why?"

"Oh, she said she wanted to fix it up herself, dear," Mrs. Hudson said. "I told her as long as it wasn't anything too drastic or permanent, she could do whatever she pleased. Maybe it'll be easier to rent next time around."

She paid cash for the flat and she even was putting out her own time and money to make it a decent place to live. She wanted to stay there very badly…

Sherlock came back late that night and settled down in an armchair, the same armchair the girl had been in earlier that day. As soon as he sat, he froze, stiffened, and inhaled slightly. John watched him, wondering if Sherlock would be able to figure out about the girl without being told.

"Someone was here," Sherlock said slowly, looking around. "They didn't touch anything. Female, probably a slightly younger than us, wearing a hat or a coat which covered her head somehow…. Did you happen to see her?"

"Yes, I did, actually," John said casually.

"Here for a case?"

"No, she's renting 221C," John remarked, looking up at Sherlock's mildly surprised face. He savored that expression for a moment. Sherlock surprised wasn't something which happened very often, and when it did John was always sure to make at least a mental note of it. "She said you would know her, and she was waiting for you, actually, but she said she had some things to do and asked me to tell you she was here."

"And?" Sherlock prompted shortly. "Who was she?"

"Elizabeth Coppens."

To John's surprise, Sherlock, who had begun pacing rapidly, fiddling with his phone, actually froze on the spot, dropped the phone, and stood like that for a moment, stiff as a statue as if trying to decide if what he had heard was actually what had been said.

"Ella? Are you quite sure?"

"She called herself Elizabeth Coppens, yes. That I'm sure of."

Sherlock spun around, eyes wild.

"Petite, probably about five feet, two and three quarter inches, somewhere between one hundred fifteen and one hundred twenty pounds, dark red, curly hair, straight teeth with slightly sharper than normal canines, bright green eyes with a small brown rim around the pupils and rather fuller, darker lips than the average female without any lipstick whatsoever?"

John blinked.

"Yes," he said slowly. "Yes, I suppose that's her exactly."

"That's impossible," Sherlock said, pacing rapidly once more, not even bothering to pick up his phone, which was still lying on the ground. "She can't have found me. I was very careful. Unless…"

He froze again, picking up the phone and rapidly typing away on it, clearly either looking something up or texting. John was guessing it was the latter.

"I'm sorry," John sighed, "but who is she?"

"She's someone I didn't want to find me," Sherlock said sharply. "And apparently she somehow did."

"Criminal?"

"Hardly."

"Family?"

"Not in the slightest."

"She said Mycroft would know her as well."

"Of course he would, the meddling swine."

"Right."

John really wasn't sure what to make of the girl, especially knowing that she wasn't family. Any other man and John would have thought she was a lover, the way Sherlock so readily and thoroughly described her, but this was Sherlock Holmes. He didn't believe in the usefulness of love, or even sex.

"I see you've found out that Elizabeth's back in town," said a voice from the door. Mycroft. Sherlock whirled around and glared at his brother.

"You told her where to find me."

"I gave hints and suggestions. She's a very clever girl, Sherlock," Mycroft said casually. "She figures things out nearly as well as you, but she hardly was given enough to find you, even by me."

"She was taught by the best," Sherlock said his left eyebrow quirking upward ever-so-slightly. "I think you underestimated her, as you always did."

"And you always overestimated her," Mycroft drawled. "But that is neither here nor there. She's here now. What are you planning to do about it?"

"What, no advice for me this time?" Sherlock snapped with a surprising amount of venom in his voice. "Perhaps you'd like to tell me how to live my life again, tell me how I should treat her, what she needs, what she deserves. She's not a child, Mycroft; she's a woman, and a very capable one at that. You know, and knew, perfectly well that if she ever wanted such things, needed such things, that she would have and could have asked herself."

"Could have, yes," Mycroft conceded. "But you know perfectly well that she would never have asked. She idolized you. I believe she still does."

"It's been years," Sherlock said dismissively.

"You hold her to your standards for yourself," Mycroft said. "She's not you. She might wish to be, she might try to be, but she is not you." He paused, letting his words settle over the room before nodding to John, and turning and walking away.

There was a stiff silence in 221B for what felt to John like a very, very long time. Finally, he said, "But who is she?"

Sherlock shook his head, sank into the armchair, inhaled deeply, and stood back up, pacing once more.

"An old friend," he said sharply, which made John even more confused.

Sherlock didn't have friends. Sherlock hardly ever even used the word to describe other people. This girl, whoever she was, must be incredibly special, incredibly important, to merit such high praise from Sherlock Holmes.

John blogged for three hours while Sherlock paced 221B frantically, occasionally pausing to say something completely undecipherable before commencing his silent, urgent pattern that he was walking into the floor. Mrs. Hudson brought them dinner, but Sherlock didn't touch a bite of it. It wasn't until nearly eleven at night when the door to the street opened and the sound of less-familiar footsteps made their way up the stairs that John turned around, Sherlock froze in his pacing, and they both watched the door to 221B expectantly, knowing that the figure about to walk through the door was the small frame of Elizabeth Coppens, the mysterious "friend" of Sherlock Holmes and the renter of 221C.

Sure enough, it was her, dark coat drawn around her tightly and slightly damp. It must have been wet outside at some point while she was out. John had been so preoccupied with his thoughts that he hadn't even noticed the weather, despite having been facing the window as he blogged.

"Ella," Sherlock said in a slightly shaken sort of voice that John couldn't recall having ever heard. "Ella."

"Sherlock," she said coolly, with excitement clearly bubbling just beneath the surface. She held her hard exterior for what felt quite long, but was probably only a matter of seconds before dashing across the distance between the pair of them and wrapping her delicate arms tightly around Sherlock's torso. To John's surprise, Sherlock vigorously returned the hug, pulling her even more tightly against him, his long arms engulfing her tiny little frame in a way that would have been threatening if it hadn't been so obviously tender. John had only seen him this way with Mrs. Hudson, and not even so obviously.

"You left," she said through tears as she pulled away from the hug finally. "You just left, no note, no explanation, nothing. I thought you'd come back. I thought you'd gone off to take care of something and just forgot to tell me, but you never came. I waited for months, Sherlock. I asked Mycroft, but he was always hesitant to tell me much of anything. He thought it was a nice little game, giving me little pieces of information, but never the whole picture."

"I had to go," Sherlock said simply.

"No you didn't," she snapped at him furiously. "You know that's a lie."

"It's not, Ella," he sighed. "I had to go. And I wish you hadn't found me. I didn't want you to find me. Things had gotten out of hand, and you know it."

"So that's just your answer for things now?" she hissed. "Things get a little bit uncomfortable so you run away and try to start over, leaving behind everything? You just find a new flatmate and move to a different part of London and continue on like nothing ever happened and the life you'd been living was just a very pleasant sort of dream you once had? It may have been a nice little thing for you, Sherlock, but to me it was everything! You were my life!"

Now John was starting to get very uncomfortable, feeling very much like he was interrupting a pair of lovers as they talked about a rather painful sort of break-up.

"That's precisely the problem, Ella, I was your life," Sherlock said softly. "I shouldn't have been. You needed more in your life than me, and you weren't going to seek out the things you needed if I was always right there. You couldn't just stay with me forever."

"Why not?" She said desperately. "I wanted to! I would have! Even Mycroft–"

"Mycroft was using you like the horrid snake that he is!" Sherlock roared. "He wanted me to live a normal life, to be answerable to the sort of powers he devotes his life to, but I refused! He thought by tying me to you he'd accomplish his goal, but don't you realize that he was willing to sacrifice your life, your happiness to make me fit his ideas of what I should have been?"

"You think I don't know that?" she said softly, green eyes flashing. John had dated enough women to know that such a look was incredibly dangerous. "You think I wouldn't have let him use me if it wasn't what I wanted? I was, after all, taught by the best."

"Ella, please," Sherlock said, his voice desperate and broken-sounding. John could hardly believe his ears. He certainly wouldn't have believed it if he hadn't heard it himself. "My life is so much more dangerous than it was, and I can't just calm it down because you want to be here. I don't want you getting hurt. I don't want anything to happen to you. Please, Ella, I don't want you to stay here. Mycroft can find you a nice place in a better neighborhood, help you set up a new life. He'd probably get you a lovely boyfriend if I asked him to–"

"No," Elizabeth snapped. "I'm not leaving. I don't care how dangerous it's gotten. You know nothing of the things I've done since you left. I'll be fine. I'm not letting Mycroft dictate my life any more than you, and I'm certainly not leaving you. It's going to take a whole lot more than your previous efforts to get rid of me, Sherlock. You should have known better. I'm not leaving. And I'm certainly not letting Mycroft get his sticky fingers into my love life. He'd probably set me up with someone horrible, like a government official or even royalty, god forbid."

Sherlock smirked slightly at this and muttered, "God forbid, indeed."

John frowned a little. Clearly, this girl had been someone Sherlock and Mycroft had known a very long time. Sherlock had left, without warning, because…because he wanted to protect her? Mycroft had done something, some sort of pressure…but what exactly had happened, John couldn't be sure of. Certainly, Mycroft seemed to both want the pair together and to keep them apart, likely depending on what suited him and his purposes at the time. Mycroft could be like that. But something about how she had mentioned the "things" she'd been up to since Sherlock left made John want to shiver, and he didn't know why.

"Sorry," she said, turning to John. "I know we haven't been properly introduced." She held out her hand and he shook it. "Elizabeth Coppens. My friends call me Ella."

"Only I call you Ella," Sherlock corrected lazily as he strolled into the kitchen. A smile played at her full, dark lips.

"That's what I said," she quipped cheekily. John could hear Sherlock pause a moment before rummaging around in the refrigerator.

"John Watson," John said, and she nodded.

"Yes, I know," she said. "I read your blog sometimes. The writing is quite good, you know."

Suddenly, he realized what was naggingly familiar about her name. Coppens, as in the famous novelists by the name of Coppens.

"Are you–?"

"Her parents," Sherlock said, sticking a cup of tea in front of Elizabeth, which she eyed warily before sniffing and sipping. "Ella has no need for a profession. She was given a large enough trust to keep her well off for several lifetimes."

John was impressed, and was about to express this when Elizabeth sighed, set the tea down, having already finished the whole cup, and said, "You still make it perfectly. It's rather late, boys, I think I'll be heading off to bed. Let me know if you need me."

"Of course," Sherlock said, kissing her cheek gently.

"Good night," John said shortly, waiting until she was gone to turn to Sherlock. "Since when do you make tea?"

A small smile played at Sherlock's lips, but he did not, of course, answer the question.

It had shaped up to be quite a strange day, John thought to himself as he pulled up the covers that night. Perhaps he would wake up tomorrow and it would all be a dream.