I got the idea after seeing this picture on tumblr.

Sherlock burst open the doors to the the jewelers, walking straight up to the counter and rapidly fired "I need a silver necklace, with a heart pendant"

The woman behind the counter, blinked twice before answering "I'm sorry, I didn't-"

Rolling his eyes, he spoke slower. "I need a silver necklace, with a single heart pendant."

"Oh! I think we can make that happen." She chirped, grabbing the key that hung from around her wrist. "Who's the lucky woman?"

Why couldn't, she just retrieve the necklace ,without chatting him up. Ugh. "My pathologist."

She scrunched her face up. "You're pathologist" She said slowly. "Um, don't they cut up people?"

Why wasn't this woman getting what he asked! Instead she rather perform small talk. Sherlock was quite sure, her employers didn't pay her for her obvious, horrible conversation skills. "Something like that. Necklace?"

"Right!" The woman, unlocked the glass and searched around. "How about this one?" She pulled out a diamond heart shaped necklace. The diamond glinting off the bright lights in the store.

Unfortunately this wasn't the heart he had in mind, for his Molly. "No"

"But it's lovely and I'm sure your... pathologist will loved it!"

"I think I'll be the judge of that. No." He tapped his long fingers on the glass, impatiently.

"Okay" Her cheerful attitude squashed, replaced by a much more nervous one. "T-this one?"

Again, not what Sherlock had in mind. It was beautiful, a simple, small, silver heart, hung on a dainty silver chain. He shook his head.

Smiling she put it back and came up with a third one. Without saying a word, she showed it to him.

"None of these will do! The heart is incorrect on every single of one of them!"

The woman looked at him in confusion. "I can assure you, they aren't."

"Really? Do you really think hearts look like that?"

She shifted her eyes "Y-yes?"

"Wrong. These 'hearts' were created by society, to make it look more appealing when wanting to express your love to your partner. Real heart's look like," He quickly tapped on his phone, showing her a picture of a real human heart. "this"

She didn't say a word, mouth wide open, staring at the picture.

"So," He squinted at her name tag "Nadine, I would like a correct heart to give to my pathologist. Can you make that happen?"

"Well... we don't carry anything like... that, but you can get a custom made one?"

"Okay." He slipped his mobile back into his jacket pocket. Spending the next hour filling out papers and talking it over with Nadine. Who felt more at ease with this very eccentric man.

Xxx

A few weeks later, Sherlock sat perched on his stool, playing with the tiny velvet box in his trouser pocket. Continuously turning it over, while never tearing his eyes away from Molly. Who sat across the room, filing some paper work. He meant to give it to her when he came in, but somehow his words escaped him and all he could utter was 'Microscope' and headed straight towards his spot, not bothering to make eye contact with her.

Hours later Molly had, had enough of his constant staring. It was making her a bit uncomfortable, with how intense his gaze was. "Something the matter Sherlock?" She asked slowly approaching him.

He broke away form his statuesque state and took an intake of breath. "Nope" Quickly dodging his head down to the microscope, pretending to be busy.

"Is that so?" Molly walked around the table, playing her fingers on the table top as she went.

"Mhmm" Not bothering to look up.

"Why were you staring at me for hours?"

He bobbed his head up to reply "Thinking" he tapped his head, then dove back down to pretending to look through the microscope.

Molly lowered herself and placed her elbows on the surface of the counter. Looking at the microscope, she smiled. "Sherlock?"

"Yes?"

"What are you so busy looking at?"

"A specimen of sorts."

"Kind of hard isn't it?"

"Hardly" He scoffed. "All you have to do is look at it like any other slide."

She rolled her eyes at Sherlock's constant need for sarcasm. "I meant, it's kind of hard to examine a specimen when there is no slide to begin with"

Sherlock's face turned into the colour of a tomato. She had caught him red handed. "Oh, I hadn't even noticed! Good eye Molly" He jumped up in a hurry, almost knocking the stool over as he went. Fumbling, he made sure the stool didn't fall. He looked up at her and smiled.

Molly could tell something was wrong, Sherlock never acted like this. "Sherlock, tell me what's wrong?" She spoke softly, stepping closer to him. Worry in her eyes.

"Nothing" he chuckled nervously. "Everything is completely fine." Like a bad habit, his hand disappeared into his trouser pocket, fiddling with the box.

Eying him suspiciously, Molly saw his hand moving wildly in his pant pocket. "Sherlock Holmes!" She shouted.

Instinctively he took a step back.

"Are you... are you getting yourself off?!" Fuming. "In the lab of all places!"

Even though, that was not what he was doing, guilt spread across his face, like wild fire. "M-Molly-"

"Oh my god! That's why you were staring at me, wasn't it?!"

"Molly" He took his free hand and yanked at his collar.

"Well, you can forget any, by the looks of it," She gazed down at his trousers and back up "much needed attention from me tonight!" She huffed.

"Oh for god's sake Molly!" He removed his hand from his pocket and stepped closer. "If I was really doing... that, I can assure you I would have been done a long time ago! After all, you should know best" He smirked. Making Molly blush. "I was simply, playing with my phone. Surely that's not a crime"

"No." She pursed her lips. "But your phone is on the counter, beside the microscope." She pointed at where it sat.

Damn. "A souvenir?" He was getting desperate. Although a tiny voice in his head, said to tell her the truth, he quickly tuned it out. He is clearly not ready to confess such a thing.

She mocked a smile. "Sherlock" She sang. "Let me see what you have in your pocket."

Sherlock backed away, slowly. "It's nothing really... just some little trinket."

"If it's just some trinket, then you wouldn't mind me seeing it" Her moves calculating as she backed him up against a shelf.

"N-no?"

"No." She whispered, as their bodies met, pressed up against each other.

Sherlock's adams apple bobbed as he swallowed hard. He took a look down at her smirking face. Molly, slipped her hand into his pocket, never tearing her eyes from his. She ran her fingers over the fabric, before pulling it out and holding it between them. She stared at it for several long minutes, Sherlock's face frozen in terror of what she would say. Finally she spoke. "Is... is this for... me?" She asked looking up at him, her big brown eyes, wide.

Having another swallow, he laughed nervously. "Y-yes"

Her wonderfully small mouth hung open, in shock. His brain came to the conclusion, that it was his fault, why she was so shocked, he would buy her something. Since, he told her his beliefs on presents and romantic gestures were just something society has placed upon couples to have to do; therefore, he refused to buy into it. Molly didn't need useless material things for her to know how he felt about her, he much rather show her. He didn't hear her mind, when she called out his name in the heights of ecstasy.

"Can I open it?"

"Umm..." This was not going the way he planned. He was suppose to tell her, he loved her first before he gave her the present. Both Sherlock and Molly, even though they felt it, never really said their 'I love yous' yet. He has been itching to tell her and let her know for weeks, but wanted the necklace to accompany him in his confession. Molly slowly reached for the opening. "No!" He shouted. She jumped at his sudden outburst and dropped the box between them. "I'm... I'm sorry" She stepped back, so he could bend down to pick it up.

"No, it's fine." She replied, a nervous smile sketched on her face, she looked down at the ground.

His heart ached, watching her look like that. Wanting, no needing to fix this, he filled the gap between them and placed his hand on her cheek, forcing her to look at him. "No, it's not fine. I shouldn't have snapped like that, I'm truly sorry." He started to move his thumb, gently massaging her skin. "Molly, I … the reason why I was staring at you, was because I wanted to tell you something. Actually I've been wanting to tell you for weeks, it's just this," He held the box up. "took a few weeks to make and I couldn't imagine saying it without it."

"Saying what?" Her mouth was slightly parted and her breaths uneven.

"I love you" His eyes went wide, he was amazed at how fast and at ease he was with saying it. Sherlock would never admit it, but the reason he deemed these sorts of gestures silly, was that he was scared, scared of rejection. He is well past the sentiment argument, the only thing that got in his way, was the possible rejection that came along with voicing his feelings out loud.

Molly gasped, water pooling in her eyes. "You, what?"

He laughed. "Molly, I love you. I am deeply, madly head over heels, in love with you." He removed his hand from her cheek and opened the box, presenting a realistic, silver heart pendant, that shone in the light. "Molly whatever happens, I want you to know that you and only you have my heart. You will have that forever and always, even when I'm long ago forgotten and buried in the ground, it will still beat for you." Putting a hand up to his mouth he whispered "Metaphorically of course, considering my heart won't actually be beating since I would be de-"

Molly laughed as she wiped the flowing stream of tears from her face. "It's beautiful." She breathed. She looked up at him, wrapping her arms around his neck "I love you too" She sniffled, pulling him down for a long kiss. Neither of them wanting to be the first to break their lips apart. It felt good connecting like this, no sound, except their loving sighs and eager moans escaping, as their tongues collided. Molly was the first to reluctantly break the kiss, in need of air.

They stood there in the lab, just staring into each other's eyes, panting. Smiling Sherlock, reopened the box with shaking hands and carefully removed the necklace. He gestured for her to turn around and placed the necklace on her. As he was doing up the clasp, he said "This heart, represents mine. I hope you will wear it always, as my heart will always beat for you." His soft baritone, leaving goosebumps on her skin. Moving her lab coat's collar over, he planted a long, soft kiss to her shoulder and up her neck, until he was nibbling on her ear.

"Sherlock" She moaned, placing her hands behind her head and found his soft curls, to yank at.

After a good ten minutes paying attention to Molly, he lifted his mouth from her skin, smirking at the marks he left. "I hope you didn't mean what you said earlier"

She turned around. "Hmm?"

"About attending to my 'much needed attention' when we get home"

She smacked her lips, as she walked her hands up the trail of buttons on his shirt, landing on the first one, she skillfully undid it. "Who said anything about waiting until we get home?"

"I know there was a reason I fell in love with you" He joked.

Molly, playfully smacked him. "You fell in love with me, because I'm unlike anything you've ever seen" She purred, pulling him by his shirt to the supply cupboard.

"Indeed" He replied, slamming the door shut. Sherlock had to admit, he loved seeing Molly wear that necklace, it was a sign of their love for each other and that she, figuratively, held his heart. But nothing could compare to the feeling that welled up inside of him, as he watched it wildly slap against her bare skin, as she moved on top of him.