Author's Notes: My experimentation with one-shot genres continues. Quite a bit different from the things I usually write, I suppose.

This is a one-shot, but I might be amenable to changing it into a prequel for a series.

"Angel By My Side" is a beautiful song by Do. Please listen to it, if you haven't yet, it's very Johnlocky, if you want to see it that way.

Reviews are always welcome.

Angels descending, bring from above

Echoes of mercy, whispers of love.

Fanny J. Crosby

ANGEL BY MY SIDE

Sherlock stood on the rooftop of Saint Bartholomew's hospital, his blue-grey eyes staring at the wavering light of the city. The sun had cast a myriad of bloody streaks over the azure sky, painting it every color from magenta to cyan. Inhaling the smog that surrounded him, Sherlock closed his eyes for a moment to listen to every sound of the metropolis that enveloped him, making him feel, finally, as a part of something bigger. Something consistent and wonderfully ordinary. Ordinary. Like him.

Shaking his head, Sherlock looked on, watching lives go by as he stood there, in stasis, imagining what it would be like if he were able to have so little time and so much to do. If he were as wonderful as the people running about their lives. If he were as human as them.

His shaky fingers slipped into the pocket of his everlasting black coat before pulling out as if burnt - cold turkey. They had agreed.

Footsteps snapped him out of his reverie and he didn't turn to greet the newcomer. Measured, quiet, almost prowling were the soft hits of shoe on the roofing material.

"Mycroft."

"Good evening, dear brother." Sherlock's brow twitched in irritation upon hearing the man address him carelessly. One simply did not throw around such an honorable title, at least in Sherlock's mind. Brother had to be earned, cherished, not given out to people who did not constitute any importance.

"What are you doing here?" He asked quietly, eyeing the London streets wearily, suddenly wishing to get this over with as quickly as possible. Everything about Mycroft's presence irritated his whole being, and vexation was not a good emotion for someone like him. Come to think of it, any emotion was downright bad. "You seemed very unimpressed with me before; your sudden interest is quite... What is the word? Ah, yes. Tedious."

"You know what I'm doing here, brother." Mycroft seemed to relish in the was Sherlock's shoulders stiffened as he approached the younger man. He really did know how to drive someone mad. "This simply cannot go on, Sherlock."

With a sigh, the detective turned to look at the other man:

"What are you saying?"

"Humanity, dear brother. Humanity," Mycroft replied, now standing right next to Sherlock and looking somewhere beyond the skyline. "Your association with a certain human doctor is what is wrong. They want answers. Or rather, action."

Sherlock shook his head silently, contemplating his answer. Every reply he could think of would be the wrong one, but in this case, was there something he could do to rectify what he had done? Gazing down at the people running down the street, hurrying to catch the last bus to get to their loved ones, raising their arms up to hail a taxi, cursing as puddles sprayed dirty water at them from under the wheels of fast-rushing cars. He sometimes wondered what it would be like to be in a hurry. How did one go about worrying about having no time to do something?

"There is nothing to talk about, Mycroft. I have told you and them that I will stand by John Watson for as long as I am able to. I was appointed for the job, and I shall see it through," he finally said, watching the other man's face change to a grimace of annoyance. Finally. "It was them who told me to go and see him through his recovery, and I have done nothing if not looked after him all these months."

"You have taken it too far, Sherlock, and we all know it. You get carried away with your little projects."

"He is not a project," Sherlock said quickly, glancing sideways at Mycroft. "He is... special."

"Sherlock, they are all special. They are humans. And it is our job to care for them... to an extent. I am afraid you have long ago crossed the line and gone quite overboard. We are not supposed to feel." Mycroft sighed, knowing his words would do very little to soothe Sherlock's interest in the army doctor. "Emotions make us human. Have you looked at your wings recently?"

With another irritated twitch to his eyebrow, Sherlock turned away from the street and hopped off the banister to stand where nobody from below would see him. Barely blinking, he concentrated on remembering who he was - it was becoming rather difficult now, - and felt a small push in the muscles of his back where two feathery pinions emerged, enveloping him protectively. He had not seen or felt them for quite some time – sprouting feathers tended to make humans panic, after all – and he relished the way the wind slid past them, almost teasing him to fly. Maybe he would; John wasn't expecting him until ten. Turning his head, he glanced at his wings, barely surprised with what he saw.

"Black feathers, Sherlock. This cannot go on." Mycroft stepped around him, eyeing the random array of maybe twenty black spots on the pristine wings with disdain. "You remember what happened the last time. They were not pleased."

They can sod off, Sherlock wanted to say, but instead stood stock-still as the soldier that he was. He knew this would happen, he knew there was nothing in the universe that would have stopped his corruption, but he was completely and utterly powerless against the charms of this one human being. God, if only Mummy knew.

"Oh, she knows," Mycroft said with relish and Sherlock groaned. "And she is very displeased."

"Say what you need to say and let me go. I don't have time for this; I have somebody waiting for me–,"

"Oh yes, the good doctor. All right then, Sherlock, listen to me, and remember it all with that remarkable brain of yours, for I will not say it twice: you need to leave. Consider this a friendly warning from me. They do no know I am here, but what they do know is that if you fall in love with a human being, both of you will face the consequences."

"Consequences?" Sherlock rasped, his throat suddenly very dry.

"You will turn human, and all humans die, Sherlock. You are a prized worker, and they cannot afford to lose you. What they can do, though, is terminate Doctor Watson."

"Terminate him?"

"Permanently. Think of something; you are, after all, a genius." With a whoosh of the wind, Mycroft's presence was gone, and Sherlock was left with his thoughts.

If you fall in love with a human being...

What if it was already too late?

Shaking his head in chagrin, he turned back to the dusk flaring around the corners of the city, its beauty captivating him once again. A day would come when he would be forced to say goodbye to all of this. He would have to bid adieu to the skyline, the blazing headlights of swarthy London cabs, the strong aroma of Earl Gray in the morning, the bite of spice in gingerbread biscuits, the glare of City banks, office buildings, hotels... And, of course, the domestic bliss he had easily fallen into with John, his only consolation. Even that would be gone someday.

And that day would come very soon, he feared, remembering Mycroft's words. He would have to let go of everything he had come to hold dear, and in return, the realm of the living would relinquish its hold on him, sending him back to where they thought he belonged. Mistakes weren't only a human trait, he mused, inhaling as much of the murky air as possible and skipping off the ledge before starting for the staircase, preferring the human way to Mycroft's display of angelic power.

They are wrong. Here is where I am supposed to be. If only for a while.

Casting a sidelong glance at the rushing city around him, he slipped down the stairs wordlessly, only stopping by to harass Molly on his way to see the only person who would ever accept him, wings and all.