Author's note – Alright, I need to stop writing fanfiction. But I can't. I'm a writing addict. I hope you guys enjoy it. Anyway. This one is a little different, given that it's a crossover. My lovely friend Leila (ephe-merely on tumblr, FYI) and I were talking about how we both want Benedict Cumberbatch (who doesn't?) and she suggested we split him in 2, and I suggested that she gets Sherlock and I get Khan, and then this fic kind of happened. The characters of Leila and Edye are really extremely true to ourselves, which has been so fun doing. Anyway. I really hope you like this, so please review/follow/favorite to let me know that you'd like me to continue.

—

He was leaning languidly against the side of Coffee Beans & Co. when they met.

"Happy Valentine's day," she said, rather sardonically.

"Mm," he said, absently wondering why she was talking to him.

"How's business?"

"Dull. That's to be expected. The oxytocin release is exceptionally nauseating today. The appeal of intentionally temporary social interactions - dating, I believe, is the ubiquitous term - is something I will likely never understand."

"I agree. Want one?" She passed him a cigarette and lit it up. They stood in surprisingly comfortable silence, given that they were strangers and it was not a habit of Sherlock's to engage in mundane conversations with random girls. This one was striking, though. Defined cheekbones, raven black hair, penetrating dark eyes.

"Sherlock," he said, a cursory introduction.

She nodded acknowledgement, saying nothing.

"And you are..?" Sherlock prompted her. The irony of him giving social cues was laughable.

"Oh. Leila."

"Right." There was no "nice to meet you," and he liked it that way.

Mrs. Hudson, his boss, poked her head out the side door and warned, "Five minutes. And put that damn thing out, it'll be the death of you."

He rolled his eyes. "As long as it doesn't impact my mental functionality, I'm good."

Leila continued to smoke unabashedly, and he couldn't help but note her full lips as double helices of vapor twined in the cold February air. "My best friend's like that," she empathized. "Anti-drinking, always telling me to be safe and careful and this, that, and the other." She rolled her eyes. "Caution is not really my area."

"Me neither," said Sherlock.

"Cool."

Five minutes passed. He found he was disappointed to leave her. "I'll see you around?"

"Maybe," she said, and stamped out the butt of her cigarette.

—

Khan was struggling. Sherlock had texted him several times, something about Mum being concerned, yada yada yada. He'd always had a tendency to disappear into his books, the way Sherlock engaged in sketchy deals and questionable missions, zipping off on his motorbike and returning with a check for 200 pounds. Fifty percent of which inevitably went into cigarettes and booze.

No, Khan was the good guy to his twin brother's badass, for the most part. Quiet and reserved, though his strong sense of justice resulted in furious outbursts sometimes.

"Is anyone sitting here?"

He glanced up, disconcerted. It was nearly midnight; why anyone else in their right mind would be spending Friday evening at the library was beyond him. This girl was pretty, if quite short, and despite the shyness with which she asked her question, the smile she flashed him was warm and confident.

"Sorry to disturb you," she added.

"Nobody's occupying this seat," Khan replied.

"Thanks." She extracted a MacBook Pro and began typing rapidly, the way Sherlock did when he was hacking computer systems as a recreational pastime. This initially aroused Khan's suspicion until he peered over her shoulder and saw, to his relief, a regular Word document.

"You type fast," he commented half an hour later. She didn't reply, engrossed in whatever she was doing. "What are you writing?"

"Stories," she answered shortly.

"What kind of stories?"

"Er... fiction."

"Mm. That's enlightening."

She grinned. "Sorry, I'm kind of on a roll here."

He tossed his pen and notebook onto the table and groaned. "And I, for one, am not."

She paused, fingers hovering over the keyboard. "What are you doing?"

"Problem," he muttered.

"That's equally enlightening," she retorted.

"Fair. I take a shitload of physics courses and they're killing me a little right now."

The girl wrinkled up her nose. "My utmost sympathy. Physics was the only class that legitimately made me cry in high school."

"Hated it that much?"

"I can't even begin to describe the horrors."

"Why didn't you withdraw then?"

"I had a crush on the teacher. That, and the fact that I'm an overachieving nerd who's too stubborn to give up on much."

"Ah."

"So what's all this?" She gestured to the pile of papers and angrily scratched out notes.

"Time travel."

She raised an eyebrow. "Time travel. In the flesh."

"Exactly." He yawned and ran a hand over his face. "My group and I are trying to prove that it's possible. I take it you're a skeptic?"

"I don't not believe it exists. I just think it's a little silly to spend so much time researching something that might not even be possible. And anyway, if it exists, it exists, why the fuss?"

He looked blankly at her. "The fuss is that time travel would enable so many people to do so many important things. Think of the genocides that could be prevented."

The girl shrugged. "Touche. I guess I feel like time isn't something to be messed with, since its nature is to move on, right? Why dwell on the past?"

"The genocide thing, primarily."

She nodded slowly. "You're passionate about these topics. I like it."

He felt himself start to blush, which was absurd, because he never really cared for compliments or insults. Indifference was a trait he and Sherlock had always shared. "Thanks."

"I'm the same, you know. Only about social issues. I can be a bit mule-headed when it comes to personal opinions, fair warning."

"Fair warning" implied that they would have further conversations, a prospect to which he had no objection. "I'm Khan, by the way," he said.

She smiled. "Edye."

"Nice to meet you."

"You too. And now, unfortunately, I'd better get going. My roommate's got a nasty habit of sneaking around at night, getting into all sorts of trouble, and we have exams this week so I'd prefer her not hungover or beaten up."

Khan gave a short laugh. "Ha. Sounds like my brother."

"They'd get along splendidly, then."

He tried to imagine Sherlock associating with a girl, and failed. "Mmhm," he said, and "see you around," as she packed her things up, zipped her jacket, and waved goodbye.

It didn't occur to him until he'd finally figured out some black hole business that he should have gotten her number.

—

Sherlock blinked at Khan from across the table. "What?" he asked impatiently.

"I didn't choose to do this, you know. Mum insisted. Apparently we don't talk enough."

"I'm done." Sherlock moved to stand up, his coffee and danish untouched. "I should get back to work."

"Come on, Sherly. Stay."

"Call me Sherly again and I will not hesitate to headbutt you."

"Fine. Sherl. No 'y'." He paused. No headbutting occurred: a positive sign. "Mum's got a point, you know. I talk to Mycroft more than I do you, and we live three blocks away from each other."

Sherlock slid back into his seat with a surly pout. "I have a busy schedule."

"False. You cut class all the time to go smoke with random people."

"Excuse me? When have I ever done so?"

Khan quirked an eyebrow. "Yesterday afternoon, perhaps? A dark-haired young lady bummed you a smoke."

Sherlock didn't need to ask. "Mycroft."

"Yup."

"God, will he ever stop stalking me?"

"He cares about you."

"I'm fine," Sherlock snapped.

"Are you, though?" Silence. Then,

"For the record, I was working, and I was on break. I don't skip an excessive amount of classes, only the ones for which I have no patience."

"As in, all of them."

"We have equally brilliant minds, Khan. You're just more tolerant."

"Valid. I still think you should try to stick with it."

"Everybody's so dull and uninteresting nowadays," Sherlock complained. "I appreciate that no one's going to have the deduction abilities I do, but they could at least be fucking real."

Khan steepled his fingers beneath his chin, tilted his head in a question. "What do you mean?"

"Every single person who walks into this shop is the same. Fake smiles, fake interest, and half the girls try to flirt with me simply because I am, from an objective point of view, attractive."

"Thanks." Khan smirked; they were virtually identical, aside from the fact that Khan slicked back his hair, while Sherlock's let his curls stay rampant and unkempt. A compliment to his brother's appearance was automatically one to his.

"Don't patronize me."

"I'm not!"

"Anyway. I'm fed up, Khan. Doesn't it get exhausting for you, having all this knowledge and potential and then having to deal with saccharine, artificial personalities and insincere flattery?"

"It's not exhausting because I have an outlet for all that knowledge and potential."

"Your science time travel shit."

"You mean physics."

"No, I'm fairly certain I mean 'science time travel shit.'"

He was a lost cause. Khan threw in the towel. "I'm just saying, you might want to consider the possibility of channeling all your energy into productive things, rather than smoking and alcohol and breaking into government systems. Illegal, by the way. Can't stress that enough."

Sherlock cast him a dubious look. "Maybe."

"Think about it," said Khan firmly. "Now go back to work."

Sherlock trudged off towards the counter.

"Wait!" called Khan.

"What?"

"Who was the girl?"

Sherlock paused, turned around. Something in his demeanor shifted. "Leila," he said simply, and returned to his post at the register.