Prompt suggested by Calicar!

"First off, you can't go around barking at people. It's not polite, and it's certainly not how to get people to like you."

Sherlock was sitting on a lab stool, arms crossed and scowling. At John's insistence, he had asked Molly to help…renew his manners. They'd been out of use and covered in dust since he left the jurisdiction of the Holmes family matriarch, the dreaded Olympe. French and snobbish, Mummy Holmes had a strict code of behavior, which Sherlock was now lacking. All right, fine, it wasn't just for John. He had to visit over the holidays, which were fast on the approach, and he'd rather not be outdone by Mycroft a third year in a row for least number of scoldings.

"What if they're being idiotic?"

"Still not okay."

"What if it's Anderson?"

Molly bit her lip in thought. "Fine, I'll let that slide. To tell you the truth, I don't like him much myself. Kind of bossy."

"And an insufferable know-it-all."

"Sounds like someone else I know."

His mouth fell open. "At least I have a right to be cocky! He doesn't know what he's talking about more than half the time!"

Molly giggled, holding a hand over her mouth. "Sherlock, no one has a right to be cocky. You just get away with it because no one wants to challenge you. You're kind of scary."

He narrowed his eyes. "Scary?"

"A touch, yeah. I was unable to approach you for the first few months of our acquaintanceship. Remember?"

"No."

"Ah, well." She shrugged. "Next, you need to try to be gentler."

"How so?"

"Well, I know you're good at faking your interest in things, such as your interest in me in order to get what you want."

"I don't—" He stopped himself. "Go on."

"Ask politely, don't drop your act while you're still in the room, try to enjoy yourself every once in a while. Smile."

"I do smile."

"Genuinely smile."

He sighed. "Fine. What else?"

"Try to be more patient. You rush through everything like you'll drop dead any second or whatever you want will vanish if you don't have it right then and there."

"What if it's time imperative?"

"I honestly doubt anything will be time imperative at your mum's."

"That's because you don't know my mum."

"Is she going to have you dance?"

"Probably."

"Do you need practice? I took lessons for years."

"I wouldn't've guessed. You're so clumsy."

"Sherlock! That was rude and uncalled for!"

"I apologize. It does just slip out sometimes." He stood, taking her hand, laying his free one on her waist. "I'll start. A waltz?"

"If you think that's what there'll be, then fine," she said, looking away. Her cheeks were turning redder by the second. Sherlock grinned.

He stepped off and Molly followed. She was surprisingly light on her feet, and had more grace than he did in her step. Huh. Maybe it only showed when she danced? This was the same Molly that tripped over herself and couldn't open a jar without half the contents flying out like snakes in a can, right? How fascinating that she was a little white swan underneath all those grey feathers.

"Careful, Sherlock, you're not keeping time," she warned as he barely missed stepping on her toes. "Count in your head."

"I don't want to."

"Do it or you'll trample your partner's feet. I doubt whomever you dance with will want crushed toes." Her tone darkened on the second sentence, jealousy brimming in sweet-tempered Molly's voice.

"All right, all right."

"Sherlock, your hand is slipping," she said calmly after a few minutes, though her face was turning red again.

His hand shot back up to her waist. He hadn't been doing that on purpose, he would swear to it. "Sorry. It's just, you're short, or rather, I'm tall, and—"

"It's fine."

He shut up, concentrating on the music-less tempo of their steps.

They slowed as time past, until they were standing still in the middle of the lab, fingers entwined, a hand on a shoulder or a waist. He could hear Molly's accelerated breathing, could feel it on his chest. He untangled their fingers and pulled her into a hug, holding on for longer than necessary. "Thank you, Molly."

"You'll keep your end of the promise, right?" He voice wasn't perfectly steady.

"Be over at one tomorrow afternoon."

"Stop apologizing, it's not intimidating."

"Sorry!"

"Molly!"

Sherlock was pacing around her in circles like a shark about to strike. Appropriate imagery, since she was the target in this lesson. "You need to show teeth, become callous, and defend yourself against being constantly used."

"Does that include being used by you?"

"I don't think you can defend yourself against me," he murmured in her ear, his voice deep and teasing. He watched with a grin as a prickle ran up her spine. "Next, we have to work on the way you carry yourself. You can't slouch, ever, it makes you look meek," he said adjusting her stance. "Chin up, Molly. You need to look down on everyone, even if they're taller."

"How?"

"Has to do with your eyes. Give me your best glare."

It was cute. She was trying so hard. He laughed anyway. "You're using your face too much. Project all your loathing at me, just using your eyes."

"I don't think I can."

"Just try. For me?"

She rolled her eyes and mustered up another hard stare.

"Somewhat better. We will, however, be moving on—" He sighed. "You still don't have this stance down." He walked behind her, placing both hands on her shoulders. "You need to keep your shoulders back and relaxed, but not to a point of vulnerability. You can cross your arms over your chest, as it reads as unapproachable to the subconscious. Or, if you rather, place them here," he instructed, guiding her hands to her hips, resting his on top.

"Is this part of the stance?" she asked, moving a hand to gesture.

"Erm, no."

He tried to slide his hands back into his pockets, but Molly held them tightly and spun around, his fingers stuck in her grip. "I have had it with your constant games, Sherlock Holmes," she hissed, backing him against the wall. "I am sick of your using me and your carelessness for my feelings and your snobbery." Her grip tightened. "I'm done giving you what you want, you need to find a new playtoy," she growled with a sneer. Her eyes were shining fiercely with anger, her face livid.

Sherlock stared down at her, speechless, unable to comprehend this Molly.

Her feral snarl quickly melted into a smile and she let go of his hands. "How was that?"

"I—" He blinked, confused.

"What? Did I do something wrong?" She looked nervous. "Sherlock, are you…are you blushing?"

"No."

"What do you mean no? I can see it. Your cheeks have gone red."

"No they haven't."

"Yes they have!"

He looked around and sighed. Maybe he was blushing. Maybe her yelling at him was frustratingly attractive. Maybe angry Molly was cute. "Do you know what the next lesson is?"

"No."

He leaned in and kissed her.

"The element of surprise."