A/N: Thanks beyond measure to sevenpercent :)
Disclaimer: Not mine.
She knows that Sherlock doesn't like to be touched. It was a widely known fact. The man went out of his way to maintain distance – when he wasn't trying to be intimidating through invasion of personal space – though really, everyone who knew him worked just as hard to stay away.
Well, almost everyone.
She's seen him interact with those closest to him. She's seen the way Molly's touch is tolerated with forced politeness. She's seen the way Lestrade's friendly claps on the back are met with a genuine smile, when they aren't met with snarling. She's seen the way he actually responds to Mrs. Hudson's mothering with a hint of affection.
She's seen him with John.
She doesn't know what they'd been like, before the fall. There were rumors that they'd been 'together,' but she'd believed John when he said that hadn't been the case.
Sitting here, sipping her coffee, she watches them dance about the kitchen, bantering back and forth as John makes breakfast and Sherlock clears away one experiment and sets up another, and she believes him still.
She sees John poking an elbow into Sherlock's ribs, moving the other man slightly so he can open the drawer to retrieve a butter knife. She sees Sherlock's hand rest briefly on John's hip, keeping the shorter man in place as he reaches around the him to bin the last bits of the completed experiment. She sees John smacking Sherlock's fingers as the detective fiddles with the settings on the toaster. She sees Sherlock place a hand on the back of John's neck, ducking him down to open the cupboard over his head and grabbing a beaker from the top shelf.
There is nothing sexual in these small touches. Nothing romantic. The hand that John ruffles through Sherlock's curls as he puts a plate in front of the other man is just … there. Casual. They are, simply, completely at ease with one another.
She feels privileged to witness their intimacy.
Sherlock catches her watching and quirks an eyebrow up. She grins at him. Finishing her coffee she stands and moves to put her mug in the sink.
"I'm off, then," she says, leaning in to kiss John, who hums into her lips.
She turns to go, pausing briefly at Sherlock's elbow. She bends slightly and brushes a quick kiss on his cheek before she can stop to think about it. He stills at the touch, but doesn't pull away. She smiles as she stands and moves past him, out of the kitchen, to grab her coat from the back of John's armchair. As she shrugs it on she turns to see similarly bemused looks on the faces of both men.
Sherlock breaks the silence. "Have a good day, Mary."
"You, too," she replies, and heads out the door.
Her smile stays with her all day.