A.N: I found this buried in my hard drive. I think it's the very first Sherlock fic I ever wrote. It was for the kinkmeme, asking for a vampire!Sherlock who needed John's help dressing because he couldn't see himself in the mirror. I just can't say no to vampires!
The vampires I used in this were inspired by the ones Susan Hubbard has in her books, in case anyone was wondering about the oysters. (I could totally see Sherlock being this type of vampire, down to the Synthasia. It's also my personal theory that in this canon, Sherlock was sired by a man named Moran under orders...)
Apologies that this was mostly "Hey I'm a vampire," and not "Hey, come dress me!"
It had taken John a while to figure out why Sherlock never ate. The consulting detective claimed it was because food slowed him down, and that was the half truth. Digesting the food did slow him down- what he never mentioned was that he didn't need it in the first place.
John wondered many times if Sherlock was half-hoping he'd deduce what he was. But he couldn't rely on traditional myths. There were never any pints of blood hanging around the flat (One's that weren't being used in an experiment, anyway) or bats flying around and Sherlock never flinched at crosses or garlic and when a thug had tried to drown him in the fountain of holy water during a confrontation at the victim's church he hadn't done anything besides cough up water and look annoyed.
No, what Sherlock considered to be John's first clue was the night he came home early after a horrible date and found Sherlock and Mrs. Hudson sitting at the kitchen table halfway through a large platter of oysters.
"I bet your dinner's better than mine," John had said at the time, passing them to grab a beer from the fridge.
"Sherlock looked a bit pale," Mrs. Hudson replied. "I threatened to raise the rent if he didn't eat."
"You do look better," John said. "If you like seafood we can skip the Chinese." It'd be worth it just to actually have a meal with him.
"Not all seafood, I'm afraid," Sherlock said, his eyes focused on John. John recognized the gaze as 'I'm giving you a hint, John Watson, let's see how long it takes you to figure this puzzle out' and felt far too tired to deal with it. He settled into his chair and flipped on the telly, finding some trashy show so Mrs. Hudson could gush and Sherlock could yell at the idiots onscreen.
The other clues were spread out- Sherlock seeming to disappear into thin air, the contacts that didn't seem to owe Sherlock for absolving them from a crime, or even the rate at which he recovered from wounds. After the confrontation at the pool Moriarty's body had never been found and Sherlock, despite taking the brunt of the blast to shield John, somehow managed to be discharged from the hospital the day before John was let out himself.
It wasn't until John was trying to fix the settings on his new phone that he realized just what Sherlock was. He was flipping through the functions, managed to get stuck in camera mode, and just as he tried to exit the menu he accidentally took a picture of Sherlock as he passed through the room. Sherlock had frozen and looked surprisingly like a deer caught in the headlights, watching John as he found the resulting picture so he could delete it.
John was surprised to find that the picture only showed a sideways view of the fireplace, completely devoid of the man in front of him.
"That's odd," John muttered with a frown, hoping that there was nothing wrong with his camera.
"Is it?" Sherlock asked, even though there was no way of him seeing the picture.
John glanced up at him. "Don't tell me you figured out that the picture was distorted by the way the screen reflected on my face."
"I don't need to see the picture," Sherlock replied. "I won't be in it."
"Why not?" John asked. "I mean... you do know how cameras work, right? That wouldn't just be useless knowledge would it?"
Sherlock frowned at him. "Of course I know how they work. How else would you be able to detect a forgery or trick of the light?"
"Then you're saying you don't show up on camera?" John asked. "What are you, some kind of vampire?"
"There is only one kind of vampire," Sherlock corrected before turning into the kitchen. John waited, patiently, for Sherlock to continue and rant on about a particular type of disorder that allowed him to rule out a particular suspect in a case, but all the man did was pull a vial of what looked to be urine out of the microwave.
"Sherlock, there's no such thing as vampires," John found himself saying, feeling slightly out his depth when all Sherlock did was glance sharply at him and laugh. "It's just not possible."
"When you when you have eliminated the impossible, whatever remains, however improbable, must be the truth."
And that was how John Watson found out his roommate was a vampire. Of course, Sherlock actually made more sense this way, so John settled for discovering the ins and outs of vampirisms.
It turned out, for one, that vampires had formed a support network, so Sherlock found just as much information from them as he did the homeless people of London or his many clients. So Sherlock went to a special doctor, took different medication, and even had his own tailor. The oysters were a type of food, giving him the same nutrients as blood. He could eat other foods, which was why Mrs. Hudson so often did their food shopping now. John had always picked up the wrong things. (Mrs. Hudson turned out to be a vampire as well, which explained why she didn't mind having Sherlock and John running in and out dragging characters of different reputes along with them)
But what fascinated John the most was Sherlock's clothes. He had a few normal outfits, ones that he had gathered for cases and such. But most of his clothing came from a particular store on the other side of London. One that, Sherlock explained, would turn invisible along with the rest of him.
"And that's how you've been sneaking away?" John asked, raising an eyebrow. "You can literally turn invisible?"
"When it's an advantage, yes," Sherlock replied. "It doesn't always work, of course. Someone could still hear me and if there's any sort of heat vision involved-"
"Can you see yourself in the mirror?"
Sherlock waved the question away, focusing on his phone as he texted Lestrade the answer to his latest case (If the neighbor owns exactly three cats arrest them). "If I felt the need to, yes. But it takes concentration that could be better spent elsewhere. If I ever need to look presentable I'll just have you dress me up."
John had chuckled, thinking Sherlock was joking. He should have known better.
"Are you sure my tie is straight?" Sherlock asked, staring down at his tuxedo front. John sighed, adjusting the little back bow slightly.
"Yes, Sherlock," John said patiently, hoping that Sherlock would get the information he needed at the gala tonight and that, god willing, they wouldn't be chased or captured by thugs or anything that would risk the deposit they had to pay on the tux rental.
He should have known better, because when Sherlock wanted to investigate another room in the building he simply left the tux balled up in the corner of the men's room. John knew he should have insisted on one of his special suits.