They have to wait a little while before a cab rounds the corner, Sherlock supporting Y/N with a hand at the small of her back.
Spying potential customers, the black beetle-like car scuttles over eagerly as soon as Sherlock gives a wave.
He regards the driver carefully before opening the door; a habit he seems to have developed after an incident that transpired about a year ago. It had to do with a cabbie, some pink pills, and Sherlock's previous roommate, who, thankfully, proved to be a rather good shot.
That roommate had moved out several months ago---with a girlfriend Sherlock can't remember the name of---which is a shame. He'd been a valuable ally on cases but, most of all, Sherlock misses having company.
For a flat in central London, it can get awfully quiet at night.
Deeming the taxi driver to be trustworthy, Sherlock carefully directs Y/N's head away from the door jamb as he helps her into the back seat.
Y/N tells the driver her address, stumbling over some of the more complicated syllables, and Sherlock tries to pull her seatbelt across her chest while she's swaying around.
...
Sherlock had wanted to spend time with Y/N outside of work, but he hadn't imagined it like this; in the back of a taxi cab, riding in silence, Y/N staring blankly out the window.
The streets slide by, neon signs of bars and restaurants, people laughing, huddled together against the cold---
Y/N doesn't seem to see any of them, their existence nothing but a brief reflection across her eyes.
Sherlock notices them; mostly couples, people his age walking hand in hand, snuggled up on benches to watch the traffic go by. A strange empty feeling begins to pool in his chest---
---but then he feels something warm at his side.
Y/N is leaning against him.
A smile ghosts his lips.
This is how he'd imagined it, he realises; when he'd pictured them spending an evening together.
The back of his neck heats.
He'd like to put his arm around her.
...
The driver nods tiredly when Sherlock passes some notes through the window, then disappears into the night, leaving Y/N and the detective alone below a broken street lamp.
Sherlock had always wondered what sort of place Y/N lives in. He'd pictured one of those colourful rows of quaint victorian houses, Y/N's the brightly coloured one somewhere in the middle, squashed comfortably between its neighbours like books on a shelf.
But, standing before Y/N's home now, he sees a block of unpainted flats, identical apartments stacked on top of each other like those grey sandwiches in Scotland Yard's vending machines.
He doesn't like imagining Y/N here; hurrying down these dark streets at night to pop to the off-brand convenience store, being irritated by the footsteps from the flat above, and yelled at for having loud footsteps by the people in the flat below. He'd noticed on the drive here how far she has to commute to get to from work---and he doesn't like the look of that alleyway.
For a moment, a suggestion of taking the spare bedroom at 221B rises in his chest. Mrs Hudson would love her, he knows. She doesn't have a daughter, but he has a feeling Y/N is exactly the sort she would have liked to have had. And he would like her to move in. To wake up to her having breakfast at the little kitchenette. To see her snuggled up on his sofa with a book in the evenings. To cook meals together and---
---but he pushes it back down.
Even if she accepts, she probably wouldn't remember it tomorrow.
...
When they step into Y/N's apartment building they find the elevator sealed with yellow tape.
"Lifts broken," Y/N states helpfully, and Sherlock's lip twitches despite himself.
"You'd make a fantastic detective, Y/N, Scotland Yard is lucky to have you."
Y/N snorts from by his side, and Sherlock directs her hand to the railing lining the staircase.
It isn't long into their climb that Y/N lets herself lean against the solid pillar of Sherlock's body---lets herself or stumbles, he isn't quite sure---but he steadies her all the same, floor after floor.
Sherlock is pretending he isn't out of breath when they finally reach Y/N's front door---just in case she isn't too drunk to notice.
She doesn't seem to notice, because when she manages to locate her keys, she jabs them against the lock six times before Sherlock eases them from her fingers and takes over.
He pushes the door open and steps back respectfully, letting Y/N enter first.
He's never been in her flat, but he decides now, flicking a light on, that he likes it.
It is a vast improvement from the cinder block hallway preceding it.
Movie posters brighten dull walls---Sherlock hasn't seen most of them but, now that he knows Y/N likes them, he's finding he has a strong urge to give them a try. Mismatched furniture jostles elbow to elbow in the small space, heavy with decorative pillows and snug-looking blankets. Y/N has nestled pot plants into hanging macrame holders to liven up bare corners, and a few squat little cacti wait for sunup on windowsills.
And, as Sherlock had envisioned, she owns a lot of books.
They're everywhere, the shelves overflowing onto desks, coffee tables, the kitchen counters, each page wonderfully soft and ragged.
Sherlock is busy admiring a messy copy of 'The Book Thief'Â Â when he hears a floorboard squeak in the next room.
Raising his head, he realises Y/N has wandered down the hall leading off the kitchen.
"Do you need any help getting into bed?" he calls, setting the novel back down.
Y/N had stuck a receipt into it as a bookmark and he'd been amused to find out it was printed with the Waterstones logo and listed with yet more books.
He follows her, his long legs catching up with her tipsy stumblings quickly, but stops when his feet meet with the end of the hallway. He dithers self-consciously, his toes gripping the carpet, inches from forbidden, uncharted territory:
A step away is Y/N's bedroom.
Y/N is on the bed, struggling with her shoes. She can't seem to get them off---because it hasn't occurred to her to undo the straps---and her body perched on the edge of the mattress is slowly falling---falling---falling---
Sherlock darts forwards and gently props her back upright. When he'd slipped both shoes from her feet he stands, one in each hand. "Where do you want these---?"
Y/N is already wriggling under the bedcovers, fully clothed, the duvet pulled clumsily up to her chin. "Anywhere's fine."
Sherlock gives her a smile without realising---because she looks cute, he thinks, making herself into a sort of disorganised burrito---and places the shoes somewhere she won't fall over them later.
There's a silence, long enough for Sherlock to think Y/N might be drifting off to sleep, and he turns to leave, switching off the light.
But then, from the dark:
"Wait."
Hand still on the switch, Sherlock flicks it back on. "Yes?"
"Can we just talk for a bit?" Y/N asks from the bed. She looks smaller, wrapped up in her patterned duvet, no crisp lab coat or stacks of official-looking documents weighing her down.
An image of climbing into the bed with her, her curled up next to him, sleepy-eyed and vulnerable, blossoms in Sherlock's mind and---disgusted at himself---he firmly shoves it away.
Crossing back to the bedside, he sits.
"We never talk," Y/N says sadly, and his brow furrows.
"We talk nearly every day."
Y/N shakes her head and it ruffles her hair into a messy halo on the pillow. "Never about important stuff."
Sherlock opens his mouth to counteract, but closes it again, realising she's right.
It's hard to talk to Y/N about important stuff. Whenever he tries, she goes red, her eyes running away from his.
She's not red now, though. She's looking at him earnestly, her gaze unfocused but steady.
He gives her a smile. "What do you want to talk about?"
She hesitates for a moment and Sherlock wonders if she's going to shrug with an 'I don't know, whatever you want' sort of gesture.
She does that a lot.
He'll ask her if she wants some lunch and he'll say 'Only if you're having something'. And then he'll ask her where she wants to sit and she'll say 'wherever you like'.
She acts like she doesn't want things, but Sherlock knows she does.
He's spent many weeks trying to weasel out what exactly they are.
"You were right," Y/N says somberly, interrupting Sherlock's train of thought.
He's alert now, interested, but he doesn't want to scare her away. Gently, he prompts:
"About what?"
"I was sad. Earlier." She does look sad. She's looked sad since the party but it's clearer now, her wilted expression illuminated by the bedside lamp.
"Why were you sad?"
"Because I've never done anything." She sighs. "I'm nearly thirty but I haven't...done anything."
Her admirable career flies through Sherlock's brain like a highlights reel, and he frowns. "You've done loads of things."
"No, not job things. Other things. I've given up trying now 'cause it feels like it's too late."
"Too late for what?" Sherlock asks, moving closer to her on the bed.
The mattress dips a little below his weight and Y/N falls into it a bit, but she doesn't seem to notice.
"At the party earlier, everyone was talking about...you know...their past hookups and stuff." She's twirling a loose thread from her duvet around one finger, winding it around and around and then letting it go.
After a little while, when she doesn't continue:
"...So?"
Limply, her hand falls back down onto the covers. "So I couldn't join in."
Sherlock blinks at her, surprised. "You couldn't?"
She shakes her head. "Not at all. They all had stories, you know? They'd done stuff---even Mark had that affair at that comic book convention." She sighs. "I couldn't say anything. I haven't ever...done that sort of stuff."
Sherlock turns this information over in his head. In the time that he'd known her, Y/N had never mentioned past relationships, but he'd never actually considered the reason might be because she's never had any. He'd assumed she's shy, or simply discreet---which he'd appreciated. For some reason, imagining her with various men filled him with an angry emotion he doesn't like.
Thinking about it now, though, Sherlock finds several things about Y/N slotting into place, the main one being her almost painful insecurity. Spending years under the impression no one finds her desirable is certain to knock her confidence a bit.
Sherlock knows first-hand.
"That's okay," he says uncharacteristically softly. Silently, he debates whether he should let go of a secret he's been clutching to for quite some time. "...I couldn't join in either. I've never even kissed someone." He forces a smile and tenderly tucks some of Y/N's hair behind her ear. "It's nothing to feel bad about. If it happens, it happens."
He'd told himself that a lot over the years, so often the words are almost wrung dry of meaning, the sentiment growing more and more half-hearted as he went from sixteen to twenty to twenty-five to thirty.
Y/N stares up at him, her brows pulled together.
She has so many more facial expressions when she's unguarded, Sherlock notes.
"You haven't?"
He shakes his head.
Y/N looks like that fact baffles her. "But you're gorgeous," she stretches the word out as if sometime around the middle she'd forgotten how it ends and then remembered again.
Sherlock feels his lips ghost with a grin, but it falls away.
She's drunk; she doesn't know what she's saying.
"I think you should get some sleep, Y/N." He's about to stand, but something stops him.
Y/N's fingers are closed on the lapel of his jacket.
He opens his mouth in question, but she's tugging him as if to whisper something in his ear.
Pliantly, he lets himself be dragged down until he can smell her soft perfume---
---and then her mouth is on his.
Sherlock's eyes widen, his breath catching in his throat.
He should pull away, he knows, that much is for certain.
She's just drunk, she's just lonely---
But he doesn't want to pull away.
Her lips taste of fruit punch.
They're soft and innocent, her fingers loosening to splay at his chest.
He lets his eyes close.
Tenderly, the spread of Sherlock's palm moves up to cup the line of Y/N's jaw.
When she releases him, his cheeks are pink, his expression pleasantly startled.
"There." Y/N grins lopsidedly from the pillow. Sleepily, she turns onto her side and pulls the duvet up to her chin. "Now we've both kissed someone."