Disclaimer: This fanfiction is not written for profit and no infringement of copyright is intended. Not beta read so all mistakes are mine.

#BumRap

You," Sherlock slurs gleefully, "are obsessed with my bottom."

"Am I, now?"

And Molly Hooper grins at him, crossing her arms over her chest. Watching him sway lightly in the (very mild) summer breeze. It's 10.30 at night and she has just answered her doorbell, only to see John Watson and Greg Lestrade pelting their way from her door, leaving Sherlock leaning against her porch like a rather stiff log.

At least, she muses, this probably means that Mycroft's stag do went well.

Their car is tearing away in a plume of dust, leaving one (apparently very drunken) Consulting Detective in her custody and grinning at her goofily.

When she makes no move to let him in his brows pull together, a pout forming.

"Aren't you going to let me in?" he asks. "You can't stare at my bottom if you don't let me in."

Despite herself, something wicked occurs to Molly. She bites the inside of her cheek and leans into him. Her tone is conspiratorial.

"But if I do that," she points out sensibly, "then when you come inside, you'll sit down, and then I won't be able to stare at your bottom, now will I?"

Sherlock's frown darkens as he considers this. "That's true," he allows. "And I suppose if your obsession with my bum is getting me through the door, then hiding it against a sofa is of no use to you: Maybe I should just promise not to sit down..?"

Inspiration clearly hits and his eyes light up.

"Or maybe I should let you get a good enough look now, so that you won't mind when I come inside and you can't see it anymore!"

And- unbelievably- he actually starts undoing the buttons of his trousers.

Molly's forced to cover her mouth with her hand, lest a truly ego-destroying peal of laughter escape.

Taking this as encouragement- though God knows how- Sherlock shoots her what he clearly believes is a sultry grin and turns on his heel, humming something which sounds suspiciously like What's New, Pussycat? under his breath and shaking his hips. This causes his arse to bounce back and forth in time to the rhythm.

It's completely ridiculous and yet strangely hypnoticc.

For a moment she stares, caught, indeed, by the sight of a part of his anatomy that she has thought rather a great deal about- But before Shakin' Sherlock can work his full magic on her a sliver of bare pale flesh peeks out from below his waistline. Turns out he's started to pull down his trousers, presumably so she can get a better look at his rear end.

With a hiss- "Sherlock!"- she grabs him and yanks him inside, causing him to grin at her in triumph as he leans back against her hall wall.

"You see?" he crows. "You do like my bottom!"

Molly opens her mouth to contradict him, but at the last moment thinks better of it.

He does, after all, have a point.

"Go in there," she points to her sitting room. "I'll make you some coffee- And for God's sake, keep your trousers on."

He nods contentedly in agreement, shuffling in through the door and throwing himself melodramatically onto her sofa. Letting out a huff of breath.

He grins at her and blows her a kiss as she closes the door.

By the time she comes back with his coffee he's already facedown and snoring, his cheek pressed into her sofa cushions. His shoes slipped off, sock-clad feet tucked against the chair's armrests. But- presumably for her benefit- he's pulled down his trousers and underpants and has arranged himself so that his bare bum is visible, no matter where in the room one might be sitting...

Molly can't decide whether to be touched or mortified so she settles for something in between: She takes a photo of the sight before her and sends it to Mrs Hudson. Then Anthea. Then Sally Donovan.

Finally, after a moment's thought, she sends it to Mummy Holmes.

For weeks after, everyone will keep grinning at Sherlock whenever Molly comes around and not knowing why will drive him bloody insane...