There are two secrets Sherlock intends to take with her to the grave. They are, quite plainly, unutterable.
The first is that she was born misaligned with her physical form and has spent the greater part of thirty-five years flowing through selves until eventually becoming who she is now, a woman within and without, a warrior whose body has been augmented and torn open and put together again, a diamond-minded specimen of fought-for gender expression.
The second is much, much worse. It is an amalgamation of every great disaster in recorded history—with the frantic tenor of the 1960 Valdivia earthquake; the dread of the Titanic's collision with its fatal berg; the screaming alarm of Vesuvius erupting hotly over Pompeii. It fills Sherlock's upper belly with so many beating wings she thinks she might be floating off the face of Earth, or dying, maybe. It makes her feel as if her chest is filled with coils of live wire that someone is touching, caressing.
No. Correction. Not just someone.
A very specific, entirely heavenly someone, who wears jeans with snags in the knees and takes her coffee unsweetened and shoots guns with such obscene, heart-racing pleasure one might think her heartless if it weren't for the fact that she can turn around straight after and wipe blood from the ghastliest of wounds in a state of starry tenderness. John Watson, she's called, in this universe at least: Captain, healer, slasher of barriers and blocks, lioness.
And here's the rub: Sherlock is in calamitous love with her.
So, to reiterate—Sherlock Holmes has exactly two secrets, and they will live and die with her. They must.
Except they don't, because the lioness sharing her flat wanders into Sherlock's bedroom unannounced one night and discovers both in a singular, cataclysmic beat.
...
Sherlock's hands are shaking and they won't stop shaking. This was stupid. This whole idea was so blindingly asinine she could vomit, but her heart is already writhing its way out of her throat and John is blinking at her, stunned wordless.
On the desk, Botticelli's Venus stares peacefully into space, her own face partially obscured by the painstaking cutout of John's atop it, extracted from a photograph taken three months previously after a particularly grueling case. In the full photo, John's arm is around Sherlock's waist and she's laughing into the wind like everything in the world is all right. At that moment, Sherlock recalls, blushing to think of John's warmth evident against her lower back even through several layers of fabric, it had been.
Now, the glue stick is unforgiving in her clenched fist, the utterly childish nature of what she'd just been doing slamming down upon her like waves of iron.
"Your breasts," John says at last. Her voice is terribly soft.
Sherlock looks down at them on reflex. Scars bracket the double mounds of flesh like violent parentheses. The sheer idiocy of allowing herself to sit topless in her bedroom with the door unlocked while pasting her flatmate's face onto one of the most shining models of female beauty known to art is astronomical. She puts the glue stick down very quietly, unable to break eye contact with John's loaded blue stare, and wishes she would die.
"I'm sorry," she says after a brief eternity, throat unbearably tight. "This isn't how I wanted you to find out."
John is still working out what exactly it is Sherlock didn't want her to find out like this, but contrary to Sherlock's frequent, affectionate jabs, she is not stupid, so the correct conclusion dawns on her almost instantly.
"My God," she breathes, without the slightest touch of anger, and Sherlock wonders how John can speak with such reverence, be so kind when she's just realized Sherlock has been lying to her all these years?
"I shouldn't have kept it from you," Sherlock mumbles jaggedly, referring to more things than one. John has certainly seen her damn craft project by now. "But I—it's so—" Many possible descriptions suggest themselves. Odd, complicated, disgusting, offensive, wrong. None of them fit, or perhaps all of them do.
Either way, her brain has reached a stalemate and Sherlock is struck dumb by John's unexpected entrance—half-naked, wielding scissors and glue, small and terribly in love. She hates herself more in this moment than she ever has, even more than the night she spent staring at her penis in the full length bathroom mirror when she was of secondary school age, gun to her temple, drawn back from the precipice only when Mycroft burst in looking for his razor.
The way he'd clutched at her, yanking the gun from her hand as though it were made of explosives is something Sherlock will never forget. His little brother died that night, forgotten forever in a rush of hormone replacement therapy and surgery and painful, powerful transformation. The woman who emerged after was made of stinging brilliance and knew how to cleave the world in two with her little finger alone. Funny, then, how that same woman is sitting here now in a state of such wretched self-repulsion.
Sherlock lets her eyes fall shut.
"No," John retorts abruptly, a fullness of pain in her voice that is both crushing and endlessly gentle. She slams her mug down on the bedside table with ferocity. "Don't you dare apologise. This is your business and you've no obligation to tell another soul."
"But it's you," Sherlock protests, desperation straining her last word into italics. "I should ha—"
"Bullshit." John comes all the way into the room and sits down very carefully on the edge of Sherlock's mattress, a vision Sherlock has imagined and longed for rather piteously for quite some time, just under much different circumstances—mellow lamplight, truths unfurled, and the swelling elation of John's lovely mouth against her own. Not like this. "You don't owe me anything. It's my fault for barging in and fucking everything up. I'm so sorry."
Sherlock moves her arm so that her elbow covers Venus. John's eyes track the micro movement, cheeks flushing visibly even in her whitening face.
Everything about her hurts Sherlock in this moment. Not on purpose, of course, but still. The very colour of John's jumper sends shrapnels of heartache spiraling through Sherlock's chest, John's Johnness slicing into her like a dagger. This is an old, familiar feeling, and if Sherlock had any defenses left she would scowl her way out of it like always, but tonight she is stripped bare in every way. She is an insect pinned to the wall for inspection, sweltering in the hot light of John's phenomenal, confounding empathy.
"Can I ask you something?" John murmurs after a longish while.
"Yes," Sherlock bites out in reply, looking down at the seam of trousers.
"Could you—did you feel like you couldn't trust me? I mean, did you think I wouldn't accept you, if I knew?"
"God, no." This is such an appallingly inaccurate assumption it makes Sherlock's stomach twist. "I'd trust you with anything."
"What was it, then?" John stands as she speaks, pulling Sherlock's dressing gown from its hook and tossing it onto Sherlock's lap. "I'm a medical woman, mind, so you're by far not the first trans person I've encountered. It doesn't faze me and for God's sake, why should it? It's an exceptional thing. But then," she adds, returning to the bed with a look coming over her face that makes Sherlock's heart thunder as if eleven consecutive bombs have just exploded inside it, "everything about you does seem to be as such."
Sherlock pulls the navy silk around her torso, hands beginning to tremble anew. John knows. John must know. She's seen what cannot be unseen, glowing palpably in spite of Sherlock's obstructing elbow, and just as she put the pieces together regarding the first kept truth, she has put together the pieces regarding the second, too.
It doesn't mean anything, Sherlock reminds herself, the mantra of unrequited adoration. It doesn't mean anything. It doesn't mean anything.
John cannot possibly love her back. Such a concept is stranger to her than the arrival of alien life on Earth. It's improbable. Impossible, even. Sherlock is too frantic for John's warmth and she always will be. The chaotic chatter of electrons before a tempest have no place inside that immeasurable blaze. She must learn to extinguish the flame John has ignited within her. She must play windstorm to this glorious fire, because John does not love her, cannot, will not.
So be it.
Sherlock makes herself answer John's question instead. "To be perfectly frank," she begins, rolling the material of the dressing gown between her fingers, "I believe a lifetime of internalized prejudice had much to do with it, combined with the fact that I detest being a burden. Ironic, I realise," she says dryly, "given that I am an atrociously large one."
"You're not." John leans forward, furious and compassionate and altogether breath-snatching.
"That isn't what I've been told," says Sherlock. Her elbow burns like a match has been struck beneath it. John is looking at her and she is looking back and her unkept secrets are shivering in the space between them, vibrations running along spider lace, end from end, Sherlock to John to Sherlock to John.
"Fuck what you've been told. Your particular existence is not a reason for apology, do you understand?" John is glaring at her out of love, a skill no one else Sherlock has known has ever quite been able to manage. It's rather marvelous. "I need you to understand this, Sherlock," she presses. "It's going to save your life."
Then she leans forward even further and wraps her hand around Sherlock's wrist, lifting Sherlock's arm from the desk with a wondering exhalation of breath. She doesn't ask for clarification, but the question is there.
"Isn't it obvious?" Sherlock says finally, woeful beyond articulation. This is the end of her. Here, in this room, all her ghosts roaming free. This is where John laughs in awkward pity, and gets up, and leaves Sherlock to bury herself still breathing.
But John isn't doing any of those things.
And Sherlock is not worrying about them, because John is saying, echo of the most magnificent pair of words ever to grace Sherlock's ears, "God, yes," and grabbing Sherlock's face and kissing her the way seeds burst from the germ; desirous, purposeful, thrilled.
Sherlock was born once a squalling infant male, then later constructed as a cold, dazzling female, but now she is being born a third time, as herself. She clutches at John and pulls her haphazardly down onto her lap, neither of them noticing nor caring when Sherlock's chair scuffs the plaster with the force of their enthusiasm.
They part eventually, noses pressed together, breathing. Sherlock has combusted. Incinerated. Gone up in shimmering white flame. All that's left of her now is ash and she is climbing courageously from her own remains, recreated. Reborn.
John beams at her with eyes full of tears. "You really are the best, and wisest, and most extraordinary woman I have ever known. Especially now." She laughs a little at Sherlock's look of astonishment. "Isn't it obvious?" she teases, and presses a tender kiss to Sherlock's forehead, heedless of her curls.
A/N: Thank you to the many tumblr users who came up with the idea of trans femlock, and for the headcanon that Sherlock would paste fem!John's head onto Botticelli's Venus in place of Da Vinci's Vitruvian Man! I take no credit for this. I would also like to say that I am not transgender myself, so all mistakes are mine. If this fic is inaccurate, triggering, etc., please let me know immediately.