Bite me part 1

                                    

                                          
A/n: inevitable vampire AU because vampire literature is inherently queer and I love it when it's done right. 
There were a lot of creatures hiding in the shadows, they looked human but certainly weren't when you got to know their secrets. 
The issue with being a vampire and living for thousands of years was constantly having to change identities to avoid suspicion. After a few decades living somewhere, you'd have to fake a death, move somewhere else and start fresh. All so no one would get suspicious why you hadn't aged over the years and start to put the dots together. 
Over the centuries, you'd had many identities, all over the world in different time periods. But no matter how much you cut and dyed your hair, changed your clothing style, got and then removed tattoos, there were some things you couldn't change. Your voice, your bone structure, your skin colour, your build. 
You had a name, a real one. (Y/n) (l/n). But you'd had many many false ones you'd lived as for decades at a time. The name engraved on that old, moss covered tombstone was still yours, but you'd not been called by that name in... you had no idea how long. 
Your latest identity, was that if a foreigner living in Japan. You'd not had a life in Japan yet, so you decided it's be a nice place to dwell for a while. You'd picked a name from outside the country to fit with the foreigner story, and dressed relatively casual, although in the many years you'd been around, you'd given up on what other people thought of you. So you weren't afraid to wear things you enjoyed even if they seemed a bit mismatched or alternative to others. Life in Japan was rather nice, everyone was polite, but also very introverted and kept to themselves. Things stayed open all through the night so no one would bat an eye you only ever emerged from your apartment once the sun was down. They assumed you were night shift worker. 
Although recently Japan had been shaken up, with the whole Kira thing. You knew immediately it was the work of a death note, that a shinigami was around. You'd seen this kind of thing happen before, a few hundred years ago. Every so often some dumbass shinigami would loose a book, a human would find it and quickly fall into its allure to write. When Kira first showed, you didn't really care. Human died, a lot. All the time. Sure, sometimes it was tragic, or unwarranted, but when you yourself are undead and have been for centuries, death kind of looses all meaning to you. 
But then L showed up. That initial broadcast where he managed to track Kira's location from anywhere in the world to the heart of Japan in only a single short broadcast blew your mind. Most humans were unremarkable, they lived their lives, had their own fun, and died to be forgotten to history. But L? He was one of those humans who'd be talked about for centuries to come. Like how we still know the names and achievements of Pharaohs, Inventors and unique individuals thousands of years later in the modern day. L would absolutely be talked about for centuries to come. He could quite possibly be the smartest human currently alive, and he sure had the reputation. Over 2000 cases and never been wrong once, completely anonymous, taking dramatic measures for the sake of solving a mystery. 
You had to see this guy in person. It was a once in a blue moon chance for a human like him to show up. And in all the centuries you'd been alive, you'd missed the chances to see them while they were alive. You weren't missing this one. 
And with your centuries of skills around fake identities and forging documents so good not even the professionals could tell, you slipped your current identity onto L's radar as an espionage expert. Someone who could ensure false identities and undercover missions were done without a hitch. You'd basically been doing it your whole afterlife, you knew a thing or too.
And that's how you ended up working with L, and you were having a blast watching him in action. It was a thrill to even see the man in person, but seeing a once in a blue moon enigma of a future historical figure at work was incredible. 
What you hadn't considered though, is L is the world's greatest detective for a reason. The average human would have no idea you were living a false identity, but L? He sensed something was off about you. So he dug, and he dug and dug, uncovering a very well hidden web of secrets. 
All these people, dating back thousands of years... they were all you. The bestselling author from Italy, the tailor in France, the botanist from Hawaii, the magistrate in Korea. They were all you, at varying points in time, with a new name and style. But the same bone structure that made up your features, the same voice, the same skin with scars in the same places. L had already come to accept there was some kind of magic or supernatural being out there thanks to Kiras power and the implications of shinigami existing. But he had no idea what you were. Seemingly immortal, under varying names, never ageing from the person in their 20s. He traces all your identities back to your very first false one. Right after you'd been turned and had to start over someplace else. And he'd hit a roadblock there, he didn't have anything that could connect you to the dead (y/n) (l/n), historical records of deaths weren't well kept in times of great diseases or wars. 
Stumped, he considered just straight up asking you. But he also didn't want to potentially scare you off from him having found out something was up. But some more dots began to connect the more he observed you. 
You never left the building during the day. And if you had to, you'd wear long sleeves and bring a parasol. Coving your skin from the sun wasn't uncommon in Asian countries, hence why he didn't see it as odd until he realised you left the building more at night than during the day. 
You ate weirdly. He was one to talk with his eating habits. But you only seemed to eat when someone offered you food, you never got any for yourself. And yet, you were still a healthy weight and strength. You must be eating something when no one was looking. At first he wondered if this was a disordered eating habit, but in context... he had other inklings. 
You knew things no modern human would know, unless they were a historical expert. And you made no mention of being into history or having past jobs in the field. You were an espionage expert supposedly, not a historian with specialty in the Black Death. 
And you were pale... so so pale. Not just from the lack of sun. Your natural skin was within the human range yes... but almost transparent in places. Your veins visible in some areas and your eyes baggier than his. Even those with darker skin could be pale for their skin tone, but you were unnaturally pale for yours. 
And your teeth. He'd completely missed them at first. Because who the hell pays attention to someone's teeth? Unless maybe they were capped in gold and caught your attention. But your canine teeth were... oddly sharp. Not needle like, but... sharp. 
He knew what you were, after a while. And since you didn't seem to be here to kill everyone and drink their blood, he let it go. He let you stay, and never bought it up. But he knew you were a vampire, likely just here to live your latest false identity. He saw you as a bit of an advantage actually, since Kira couldn't kill you even with your real name. You were already dead. Unless you got a steak to the heart, you'd live. So even if he died, and all the taskforce did too, Kira couldn't get rid of you. You could be the key to solving this case...
But how did he bring up the fact knows what you are... and not scare you off? Would you be scared off? You seemed very secretive about everything, but then again, that could just be so no one finds out about your false identity and forged documents. 
L knew you were a vampire, and he wanted you to trust him enough to tell him outright. So he knew what he needed to do...
Let you feed on him.