Sherlock Holmes and Molly Hooper sat side by side on the couch in her sitting room, watching telly with varying degrees of interest. It was Saturday night and they have spent the day performing various experiments on human, and non-human, tissue. The human tissue was supplied by Molly, culled from a seemingly never ending supply from St. Bart's morgue. Sherlock brought the non-human variety, from god knows where, helped by Billy Wiggins, who arrived with a fox in early stages of rigor mortis, as well as a dead pigeon. Variety is the spice of life, as they say.

But the experiments were long over, and the two had settled into a long night of viewing, neither of them too enthused about the offerings. Sherlock had become accustomed to spending evenings at Molly's flat, and a dearth of watchable television offerings was not about to change his routine. They had sat through a couple of reruns of "The Big Bang Theory", followed by a documentary on arguments between the Queen Mother and the Duke of Edinburgh concerning the Queen's coronation. Hardly topical, but mildly interesting. Molly had decided that if anyone was a match for the Queen's grumpy husband, it was her rather formidable mother. The last couple of shows they had watched involved sex. "Secrets of Sex", a discussion of internet sex toys, hookup sites such as tinder, and virtual reality porn. The next episode investigated internet dating and finding love in the twenty-first century. Molly Hooper may have been interested if the man of her rather colorful fantasies were not sitting right next to her! Her bright red complexion was a sharp contrast to his icy white facade of disinterest. In an attempt to lead any conversation in another direction, she found herself asking the detective a serious question.

"Sherlock, what's your mind palace like, anyway?"

"Come again?"

"What's it like? How does it work?" she asked again, with real curiosity. "I heard you mention it. And sometimes John makes fun of it. But how do you use it? How does it help you?"

Sherlock looked at her, trying to determine if she was truly interested, or just making conversation. "Why do you want to know?"

"I'm curious, that's all. I know you have an eidetic memory. I know you remember just about everything important, or even not so important. But how does a 'mind palace' help you? And why a palace, anyway? Just because it sounds so grand?"

"A bit of that, I suppose. Mycroft taught me the technique, and he has a 'library', as he calls it. 'Palace' sounds so much better, don't you think?" The detective sneered a bit at his brother's inferior creation. "Basically, it's a way of representing facts in an easy to access manner. Mycroft calls his a library, but from his description, it's more like a giant filing cabinet. He can access virtually anything, but it's like heading a file. The data is all there, but his mind has to interpret it. My mind palace is more of a visual experience. I do keep files on certain topics, but my palace is populated with people, life-like images. They live, they breathe, they interact with me just as they would in the real world. Mycroft is every bit as annoying in there as he is out here. John is always ready to offer advice, whether I've asked for it or not. And they all live in my mind palace, each in their own room."

"Really? Tell me about them!"

"Well, John's room is rather large, and getting larger now that Mary and little Claire have joined him."

"They all live in there? What does it look like? Does it had a real visual representation?"

"Everything is visual, Molly. John's room used to look like the sitting room at Baker Street, but I've changed it to reflect his new house. There's a small adjoining room for Claire, a nursery with all the things she needs. I often store some new educational toy, or fluffy bunny, in there when I see something I want to buy for her eventually…"

"John's right, you know. You do spoil her!"

"I'm her godfather. That's what godfathers do!"

"I suppose so, but last month you bought her a fully operative mini-car! Pink, with an annoying horn, Sherlock." Molly shook her head with a slight laugh. "You git, she can't even walk yet!"

"Molly, be reasonable. If she could walk, she wouldn't need a car!" He spoke with a laugh. "I'm not even going to tell you what I have stockpiled under her cot. You'll just tell Mary, and ruin the surprise."

"Sherlock…", Molly said rather ominously.

"Anyway, Mycroft's room is rather unwelcoming, just like the man himself. Not a comfortable chair in sight, so I'm never tempted to linger, not that I ever would. He sits in the middle of a web of control panels, maps, phone lines, computer screens. One of the computers is Anthea, whom he fondles gently on occasion. She always responds with a shrill beeping sound, and turns off. I thought that was a nice touch."

"Sherlock!"

"Then there's Lestrade's room. Looks like his office at the yard. He has a picture of his wife, or ex-wife, depending on the day of the week, on his desk. He keeps a bottle of whiskey in his bottom drawer, and has his mobile at the ready, with my name on speed dial. Just in case. Other people just appear as needed, or even as not needed. I keep Sally Donovan in a closet. Anderson is in a small doghouse out back. I never go out there."

"There's got to be others, though, Sherlock. What about your parents?"

"Oh, they have a large, comfortable room on the top floor. It looks a lot like their cottage in Surrey, with a perpetual fire burning, and the smell of coffee brewing. With a door leading to my childhood bedroom, just in case I need to beat a strategic retreat from the world. Please don't mention that fact to anyone, Molly. I wouldn't do my image any good!" A rather self-deprecating laugh, so rare for the man, escaped his lips. "Mrs. Hudson lives in her kitchen, so she can always bake those chocolate biscuits I'm so fond of. And she serves tea each time I visit." The man paused for a moment, gathering his thoughts. "Each of these environments is tailor made for each occupant, but each person is free to leave as they wish. They are fully functioning constructs, with the qualities and characteristics of the people they represent. I interact with them just as I would in the real world. So much more practical, and a lot less boring, than Mycroft's method of simply consulting stored data."

"No wonder you spend so much time in there, Sherlock. It sounds like there's a lot to do, and people to see."

"I haven't even told you about the laboratories. And the music room. And the ballroom!"

"Ballroom?"

"What can I say - I like to dance! And in my mind palace I can dance to some of the finest music ever written, with a partner of my choosing. And, I can hear some of the finest performances ever recorded, performed by masters! I can play entire operas, and symphonies, and concertos! I will admit that I sometime get distracted, to John's consternation when he can't seem to get my attention. Others complain about that problem, too. Perhaps I should rig up some sort of alarm system, one that recognizes outside communication and alerts me to it." The look of concentration on his face led Molly to believe that she was in danger of losing him to the myriad passages of his mind palace at this very moment.

"Sherlock!"

"Yes, no need to shout, Molly."

"I thought I was losing you there. I've never had that sort of problem, though…"

"No, of course not, Molly. I always seem to hear you, even when I don't want to."

"Sherlock, you haven't said. Do I have a room in your mind palace? I suppose not, then. I suppose I'm just one of those roaming figures haunting the hallways, huh?"

"Don't be ridiculous, Dr. Hooper. I've told you before that you are most important to me. You count. You have a rather large room, as a matter of fact. It's like the facilities at Bart's, fully equipped. And there is an exit to your flat, I suppose because I spend so much time here, watching crap telly and eating takeaway."

"So, my flat, eh? Do I at least have a better telly? And newer furniture? See what you can do about that, okay? I'd like to think that my sitting room is better decorated in your mind palace than it is in the real world!"

"Not to worry, Molly. When I get around to building you a sitting room, I'll ask for you input."

"I thought you said the door led to my flat, Sherlock…"

The detective now realized that he had painted himself into a bit of a corner, and had to scramble a bit to get himself out. "It is your flat, Molly. But, it's your bedroom, not your sitting room. I guess I figured you needed someplace to rest, and store your wardrobe, after all. You're not always dressed in a lab coat, you know."

"No, I don't know. What am I dressed in, Sherlock?"

"Baggy trousers and colorful jumpers about three sizes too large, of course," he said quickly, a bit uncomfortable about where this was heading. He didn't want to mention the slinky dresses, or the lacy lingerie. Not to mention the times she wore nothing at all. He wasn't ashamed of his fantasy life, but he wasn't exactly proud of it either. "Remember, Molly, these images may be of you, but they are constructs of my mind. And that is the way I see you."

"You're not displaying much of an imagination, Mr. Genius Detective. Couldn't you come up with something a bit more attractive. A nice designer suit, some elegant evening clothes, perhaps?"

"And where would you wear these things, Molly? To the morgue? Or a night out at the local?" Even as he spoke the words, he was imagining dressing his pathologist for a night in. And the attire he had adorned her in was definitely not a designer suit. He hoped this part of the conversation was over, as he wanted no more speculation from Molly.

His hopes were soon dashed as the small woman said rather softly, "Sherlock, why is my room the only one with a bed?"

He could feel himself getting a bit flushed, but managed to recover. "It's not, remember? I told you that there was a door in my parents' room which led to my childhood bedroom."

"Okay, I can understand that. It means comfort, an escape from your day to day life. But Mycroft runs the whole government, practically, and he doesn't need a bed. John and Mary have a small child, and jobs. They are certainly exhausted, and they don't have a bed. Your parents are elderly, and could probably use a good lie down, but they don't have a bed. Neither does the equally elderly landlady, whom you run ragged, nor the overworked policeman. So why me? Do I look that tired? Do I have dark circles under my eyes? Am I that lethargic, that haggard looking, that somnolent?"

He got the feeling that she was missing the significance of the bed in her room in his mind palace, and, while he should have been grateful for that fact, he didn't like the idea that she was seemingly taking offense, as he was making a comment on her looks, or attitude. "Molly, I assure you, the presence of a bed implies none of that. You have no dark circles. You are not haggard looking, nor lethargic. You are lively, animated, vivacious, sprightly, and spirited. That's the way I always see you. Beautiful!" Sherlock worried that he had gone a bit too far when Molly began to blush.

"You think I'm beautiful, Sherlock?"

"I may be many things, Dr. Hooper, but I am not blind. Of course I think you're beautiful. Even more beautiful in real life than you are in my mind palace."

Molly's smile spread from ear to ear, as did her blush. "Then may I assume that the bed is not, per se, for sleeping, Sherlock?"

"You may assume anything you wish, Molly, but I will neither confirm or deny the possibility." The detective spoke calmly, but the pathologist could tell from the slight tremor in his voice, and the red hue slowly spreading to his ears, that she had hit a nerve.

"Sherlock, just how friendly do you get in your mind palace?"

"Very friendly, indeed," he whispered, barely audibly. But he knew that Molly heard due to the sudden catch in her breath.

"Sherlock, I don't have a mind palace, of course. But I do have an imaginary place where we do get, uh, 'very friendly' too. Perhaps we could discuss a co-habitation agreement?"

The detective began to smile almost as widely as his companion, as he moved closer to take her into his arms. "I think we can arrange something, Dr. Hooper. Would you be insulted if I were to supply, in real world terms, some of the lingerie to be found in your bureau in my mind palace?"

"Not if you aren't mad when I rip off your buttons!"

"Which buttons, Molly?"

"Does it matter, Sherlock?"

"Not at all. Rip away all you like!" he said, before smashing his lips into hers. "Saturdays are about to get a lot more lively around here, Molly, my love!"

"I don't think you'll be needing that mind palace as much, Sherlock. You'll have to settle for a cozy room and a soft bed."

"And a soft woman, I hope. And a hard…"

"Sherlock! Let's save that kind of talk for the bedroom!" She took his hand and led him quickly toward the room in question, where real world Molly certainly gave Mind Palace Molly a run for her money.