A couple of days later Caitlin had insisted on returning to her own flat. She had become adamant about returning to as much of a normal life as possible. Yes, what was happening was worrisome but she was determined not to let this killer run her life. She was not going to hide inside. Caitlin would return to work and continue living her everyday life. After Sherlock had all but ordered that she would now stay with him in his flat, in his room, Caitlin started to use her flat for work only. She smiled to herself. Sherlock. Being in a relationship with the world's only consulting detective was an adventure all it's own. Yes, Caitlin and Sherlock had established that they were indeed in a relationship, and remembering the conversation they'd had made her laugh out loud.

The night after the three had visited the police station Sherlock and Caitlin sat quietly each reading their own book. Sherlock sat in his chair, Caitlin sitting on the floor between his legs, her head resting against one of his thighs. The only sound in the room was the ticking of the clock and the flipping of book pages. John had worked late at the clinic and then was off on a date, so Caitlin didn't know when or if he would show up. After a little while Caitlin stood and stretched, setting her book down on the way to the kitchen. Feeling Sherlock's eyes on her Caitlin looked up. Quirking her lips she stated,

"Will you please stop staring at me? It's unnerving!"

Sherlock just chuckled before turning his eyes back down to his book. Pulling pots and pans out of the cupboards Caitlin called,

"Sherlock, you hungry?"

Taking his silence as a 'yes' Caitlin started to hunt for ingredients to make a simple dinner before she let out a shriek, dropping a box of pasta on the floor. Gulping in some much needed air, Caitlin turned to face an inquisitive Sherlock, a disgusted look on her face.

"Why are there THUMBS in the refrigerator?!"

Looking at her as if she'd grown a second head Sherlock stated what he thought was quite obvious.

"Where else would I put them?"

Letting out a noise of frustration, Caitlin turned to go upstairs. Hearing Sherlock ask where she was going, she just exclaimed,

"I'm going to go get the ingredients I need! I am certainly not using anything from your fridge!"

Once she'd returned, Caitlin made a quick pot of spaghetti with meat sauce, grinning when Sherlock devoured almost all of it. After dinner the two resumed their earlier places and all was quiet until Caitlin asked,

"Sherlock what exactly are we doing?"

Closing his book Sherlock glanced down to where Caitlin sat. Drawing his eyebrows together he replied,

"I'm not sure I understand."

Fiddling with the hem of his pants leg Caitlin looked anywhere but at him as she murmured,

"What type of relationship do we have? Am I-Am I your girlfriend or-"

"Would you like to be?"

Caitlin was shocked into silence as his question cut her off. Reaching down to grab Caitlin's hand, Sherlock pulled her up before tugging her to sit in his lap. Caitlin was silent for a moment before stuttering,

"W-What did you say?"

Sighing, Sherlock fought the urge to roll his eyes. Gazing at the woman perched on his lap Sherlock repeated,

"I said would you like to be my girlfriend?"

Caitlin blinked a couple of times letting the question fully sink in before a genuine smile graced her face. Leaning forward to kiss Sherlock, she answered him.

"Of course I'll be your girlfriend Mr. Holmes."

She leaned in again for another kiss when she saw Sherlock make a face. Raising an eyebrow Caitlin just said,

"What?"

Meeting Caitlin's eyes Sherlock stated,

"Don't misunderstand, I'm very pleased at your answer. It's just that word. Girlfriend. It sounds so…juvenile. I think I would much rather prefer the term lover."

Blushing, Caitlin smiled a little before murmuring,

"Whatever you want Mr. Holmes, as long as you're mine."

Smirking Sherlock caught her lips with his before scooping her up. Squeaking, Caitlin grabbed at him frantically before exclaiming,

"Sherlock what are you doing?!"

Heading towards his room Sherlock just grinned before stating smugly,

"We'll discuss the terms of this relationship later. Right now I believe I owe you a lesson."

Coloring brightly Caitlin stuttered,

"What on earth are you talking about?!"

Shutting the door to his room with his foot Sherlock set her on his bed stating,

"I believe your exact words were 'You can teach me a lesson tomorrow. I doubt I'll learn.'"

Before Caitlin could even try and utter a reply Sherlock pounced on her.

After that night Caitlin was more than happy to acquiesce to Sherlock's request of staying with him. It was hard for either party to admit, both Sherlock and Caitlin found comfort and peace sleeping in each other's embrace. While she had been sitting inside her flat reflecting on this, Caitlin adjusted the material that lay on the dress form in front. Bringing in the seams a tiny bit more Caitlin finished the last of her pinning before carefully pulling the delicate dress off the form. Taking a seat at her sewing machine, she started to hum while listening to the quiet whirring of the machine. Caitlin was excited. She had been invited to showcase some of her designs at one of the newer but very prominent fashion galleries in London. This garment was the last piece of her collection and once it was finished she could finally stop worrying. As she pulled the finished dress from the machine Caitlin heard footsteps pounding up the stairs before the door below banged open and slammed shut. Raising an amused eyebrow she just chuckled under her breath "Sherlock's home." And by the sound of it, he was not happy. Taking her time to put the finishing touches on the dress in front of her, Caitlin took it off the dress form once she was done before hanging it up. Cleaning up her workspace, Caitlin put all her materials away before she decided to lock up her flat and descend the stairs to where she knew her discontented boyfriend awaited. Arriving at the flat Caitlin rolled her eyes with a sigh before opening the door. Once inside, Caitlin started to say something but faltered as she saw Sherlock staring down the music box. The music box she had given her sister and found placed on her desk. Sherlock barely glanced at her before he continued to glare at the small object in front of him. Getting a hold of herself Caitlin sat next to Sherlock on the couch before asking,

"Why are you staring at that box as though it has offended you?"

Turning his gaze to Caitlin Sherlock muttered,

"I have looked at that thing for the better part of an hour and I can't find anything! I've run tests, searched for finger prints, x-rayed it and there was nothing! It's completely clean. This person has left no trace. It's utterly hateful!"

Caitlin was completely silent. Sherlock watched as several emotions crossed her face before she reached a tentative hand out. As her fingertips lightly grazed the polished wood Caitlin sucked in a sharp breath, struggling to retain the tears that started to form. Gently lifting the lid, a watery smile formed as she heard the soft strains of a lullaby. Caitlin faced Sherlock as she swatted away the few tears that had escaped.

"I gave this to Abby on her 10th birthday. It was our favorite song."

Sherlock covered Caitlin's hand that rested on her knee with his own. Lacing her fingers through his, Caitlin frowned with the statement of,

"I don't understand how he got this. I haven't seen it in years."

Hearing a clap of thunder, Sherlock stood and walked to the window murmuring,

"A smart criminal can find anything he needs."

Going to join Sherlock at the window, Caitlin leaned against him. Feeling Sherlock slip an arm around her waist, Caitlin continued to gaze out the window, watching as the rain began to fall. As it began to run down the glass, Caitlin left Sherlock's embrace and drifted off to the bedroom before Sherlock could say anything. Watching her leave, Sherlock never took notice of the figure that had been watching from across the street.

Pulling his coat tighter around himself, he scowled as his eyes burned with hatred. He should be the one with Caitlin, not Sherlock Holmes. Turning on his heel, he started down the street. Caitlin was everything he wanted. The first time he had seen her he knew from that moment that she would be his. He'd even gotten rid of her boss so she could have her chance to shine. Finding out that the woman he'd killed last year was her sister had been a delightful surprise. Now nothing could stand in his or her way.

However it was quite obvious now. She had made her choice. Choosing Sherlock Holmes over him had been the wrong move. She would soon learn that such decisions had consequences. Turning back to look down Baker Street the man uttered ominously,

"Goodbye Miss O'Connor. I'll be seeing you very soon."

Crossing at the corner a wide grin crossed his face and he pulled his hood up before vanishing.