The lights from the city of London shone through the early evening October fog, and as John Watson squinted they didn't look like lights at all, just colourful circles swirling and dashing by. With his reddened hands curled like claws in the cold plunged deep into his jacket pockets, he walked on and on slowly placing one foot in front of the other, after the usual route.

He'd been sent to get the shopping, which was his usual job. The doctor himself didn't really mind but sometimes he wished he didn't have to step outside into the chilling autumn evenings on his own. Then again it was mostly his fault he had to go out at six-something to the shops, as he was too forgetful for Sherlock's liking. And Sherlock wasn't the best person for walking conversations.

John looked through the small crowd of the desperate, trying to get home in time. Not one of them looked like the kind he could talk to, and no one was either, he just had to keep his head down, get the shopping and go home. Why would a task as simple as that make him so sentimental? Maybe because it was so ordinary. Something inside of him longed for gun shots, aching feet, adrenalin rushes, thrill pumping through his veins.

And then his eyes crossed over to the bridge. It looked normal apart from an added feature; a girl standing at the edge. Red tangled hair bellowing in the wind with her face facing downwards, to the river below. John's heart began to race. Not one of these cars speeding past has time to stop and talk to her. No one is telling her isn't the wrong thing to do. She's ready to jump and no one wants to know.

His first instinct was to cross the road which he did gingerly causing cars to come to screeching and he had to dart between them. John didn't want to alarm her, he felt as if he was approaching an injured animal that could snap at any second. The girl didn't seem to pay any attention to his arrival and he was left staring up at her for a few moments. Then she slumped onto her right leg ready to leap down below.

"Not again." John murmured under his breath. "Not. Again."

He grabbed her by the waist and pulled her down from the ledge. She was a little startled but she didn't resist and John wondered if she didn't mind, that she wanted to be saved. He didn't know anything about her and still he lifted her down quickly and placed her back on the pavement.

There were a few seconds where neither of them said anything. John felt it was his responsibility to start conversation but he had no idea how. He untied his tongue and settled on some words to let loose.

"Look, I don't know what your story is but it's not worth jumping off a bridge over." He said, looking her straight in the eyes. "Alright?"

Now she was standing right in front of him he got a proper look. She was the same height as him and her dark red tangled hair went just to her shoulders, parted to the side. Her eyes were either a green or a hazel and they twinkled along with the London evening. She wore a black coat and from underneath a black mini skirt peered out, teamed with teal coloured tights and ankle boots. Looks about twenty something. Black smudges sat underneath her eyes like literal emotional bruises and John wondered what her story really was.

She nodded softly, looking down as a tear rolled from her closed eyelid. "I'm sorry."

"Wha- what's your name?" He asked curiously. When she didn't respond he took a breath. "I'm a doctor, you can trust me if that's what you're worried about."

"Sorry no I just- I blanked out for a second." She almost laughed at herself for a second which was beautifully ironic as another droplet drifted down her cheek. "I'm Evanna."

"I'm John. Alright, Evanna..." John crossed his arms but tried to keep up this friendly and trusting air he was almost sure he had going on. "Why did you want to kill yourself?"

"I don't know... I want to do it alone. There's just so much inside of me, I just want it all to end I-" Evanna stopped in the middle of her sentence. "I'm sorry. I know you're a busy man, you can go now, I won't end it all tonight."

"What makes you think I have to go?"

"It just hit me, I knew I recognised you. You're John Watson. I read your blog. And Sherlock's and wow I don't deserve this I'm really not worth your time just-"

"No you are." John nodded, replacing his stance. "I couldn't let anyone jump, not again anyway. And you don't have any reason to."

"But I do."

"But you don't. There's never a reason."

"Whatever, look, I'm sorry." She stepped back a little. "Sorry for wasting your time."

"You don't honestly think I'm going to let you go home alone do you?"

"Why not?"

"Because I don't know what will happen. Feelings like that don't just go, there's no on and off switch."

"What's the solution then?"

"Well... do you want to talk about it?"

Evanna sighed deeply. "I just have a lot of little problems and one big one."

"Where do you live?"

"Two tube stations away."

"On your own?"

"On my own."

"I'm scared that if I let you go now that I'll read in the paper that you died another way the next morning."

"Then you should be relieved."

"I wouldn't."

"Why do you want to help me anyway? I'm nothing special. No one would care if I went."

"I would."

"You're only saying that because you know that I was going to do it, if you didn't then you wouldn't care. No one would."

John stopped to think for a few seconds, letting the words seep into him like blood seeping through cloth. Then he pursed his lips, nodded a little, and said something.

"You didn't get the shopping." Sherlock called, as John was halfway up the stairs.

John was about to ask how he knew without even turning away from his laptop and looking at him but decided against it. He leant against the doorway. "I brought someone."

"I know, not another girlfriend I hope, they're not very good." Sherlock stopped typing and looked up. Evanna was hiding behind John slightly, like a child hides behind a balloon at a fair. Except she wasn't nearly as gleeful. "Hello Evanna."

"How did you know my name?" She asked, crossing her arms and stepping into the light that crept through the window in the hallway. "Oh wait. I think I can beat you to this one." She lifted up her wrist, which had a loose and faded friendship bracelet tied around it. "It's on the bracelet?

Sherlock nodded distantly. "Yes..." Suddenly he felt a bit awkward. His intelligence was the way he started conversation, the way he impressed people and maybe he would need to work on it a little more if someone could guess through it that easily.

"I couldn't leave her alone so she's staying the night," John explained. "if that's alright."

"You know what isn't alright, John?"

"Not getting the shopping?"

"Precisely."

John sighed. "Do you want me to go again now?"

"Only if you want."

"Fine." John turned around conclusively, before tilting his head back to look at her. "You'll be alright if I leave you with him for a bit?"

"Yeah," Evanna smiled. "I'm sure it'll be interesting." John raised an eyebrow. "I wasn't being sarcastic!"

"Okay then, I won't be long."

After he left, Evanna was left standing in the incredibly awkward and pointless place, which was half in the flat and half out. She stuck her hands in her pockets and reconsidered her situation. She was at 221B Baker Street, shared by Sherlock Holmes and John Watson. It might take a while to sink in.

"Come in." Sherlock stood up quickly, as if he was suddenly alerted by her being there. "It's annoying if you just stand there."

"Sorry." She entered and shut the door.

"How's teaching yourself bass coming along? I suspect you're finding it harder than guitar."

Evanna blinked. "How could you tell that?!"

"Your hands. Firstly there's a pressure mark on your right wrist from the neck, if it wasn't new you'd have a strap by now. There's dents in the tips of your fingers too from pressing down on the strings. The other hand has them too but they're smaller, finer, from finer strings. You're left-handed so you play a left handed guitar which you're used to as the marks aren't as deep and you play standing up, you have a strap for it, hence the lack of pressure marks. You're finding it hard because you're not used to using your right hand for playing, in fact you can't even stretch your hand out properly any more as I can see now."

"That was great."

"Thank you. You're a guitarist."

"What else am I?"

"A song writer. That's easy, I can see some manuscript paper poking out of your jacket pocket. It's handwritten so it's likely to be your own. And a singer, you should really work on warming up. Your voice is a little husky from not doing it properly."

"Wow. You really are good." She crossed her arms. "What else can you tell about me? I'd be interested to know."

"You would. I know why you're here tonight."

"Go ahead."

Sherlock smiled at the challenge. "You were going to commit suicide and John stopped you, because no matter who you were he couldn't let it happen. You were reluctant but you went with him in the end because you knew you wouldn't get out of it anyway."

"And how do you know that?"

"Timing. He wouldn't have taken forty-eight minutes in total if you weren't stubborn."

"Good, good, do you know why I was going to do it?"

"I do know. You think you're worthless, that you're a waste of space and everybody's time. Firstly you're very thin, not anorexic but close. There have been times where you've gone for days without eating when there was no one there to motivate you. You're almost back to normal now but you want to relapse. You're scared of putting on weight. You're addicted to self-injury, it makes you feel alive and it's a distraction. When you stepped into the light I saw scars all over your legs. You're moving your arms slowly too because the fabric will rub against your scars which is very irritating. You use any type of method you can, I can tell by the way you move, different parts of your body have different wounds, that's easy. Your songs aren't published because you don't think they're good. You don't think you're good at anything, I can tell that by your attitude, like you have nothing left to lose. The starving and the self-inflicted injury is all a distraction but not for the first time, it wasn't enough."

She nodded slowly. "But a distraction from what?"

"You're traumatised."

"I am. Do you know what by?"

Sherlock was silent for a few moments. He looked straight into her eyes, the hazel and green kaleidoscopes suddenly twisting like cogs turning as he stared at them. Nothing was there. She returned his gaze and despite being considerably less clever than Sherlock – who wasn't – she saw nothing was there either, in his cold blue irises. It was frozen over, cold. She shuddered and looked away.

"You don't do you?" Evanna looked at the floor. "You can't see it can you?"

"I c-can't." Sherlock stumbled. "You're not letting me see. You don't let anyone see."

She nodded again. "Exactly. I've met a lot of people, none of them could. I sort of hoped you could, but I sort of knew I'd be wrong too. Still impressive how much you could tell though."

"You read my blog. You knew I'd be the smartest so far, why didn't you think I could work it out?"

"Because you're not really that great, are you? I mean, that brain of yours, it's a talent, but it's nothing in the real world."

"What do you mean the real world?" He sneered as he grew frustration. "We live in the real world, this is the real world."

"I don't mean reality. There are people who are far from there but we're not them. We're just a little far off, just a little bit away."

"Stop that."

"Stop what?"

"Being cryptic. I know it's not to impress me."

"You would. No, I mean that you can't be good at one thing and at another. One day that brain won't be enough. You'll need to read someone, someone like me."

"And you're saying I won't be able to?"

"Exactly."

Sherlock frowned and took a melancholy step away, watching his feet. She has to be wrong - doesn't she?! Who was she to tell him that anyway?

"Don't worry. I'm the same too. Do you think I would've gone to that bridge if any of my talents meant anything?"

Sherlock spun around quickly. "That's not fair."

"What's not fair?"

"Your game. You are letting me see what it is, aren't you?"

"How would you know?"

"I would know you."

"Aren't you supposed to be able to tell right away though? When I'm lying, when I'm not?"

"You're not like that." He started pacing feeling challenged, like he had to work this out. "I know you're hiding something just not what it is. You're not letting me see, that's not good enough, what is it?"

"Do you really want me to-"

"-NO! That's cheating and you wouldn't tell me anyway. You have trust issues."

"Well done. Still don't know what it is though?"

"Stop talking I need to think."

"You won't get it..."

"FINE!" Sherlock snapped, sending a vase flying off the mantelpiece. "This isn't fair. Stop taunting me."

"I'm not! I'm just asking a question, a question which you promise to answer."

"But I can't, and you know it."

"Maybe you can."

"Let me work it out then." He swallowed, moving closer to her. "You're challenging me, I accept. I'll work it out."

"How do you intend on doing that?"

"You said one day my observance won't be enough, well I'll expand it. You can be my experiment."