Author's note: this story is set shortly after Buffy finds out that she's the Slayer, and before the start of Warehouse 13. I do not own either of these shows, and I will never do so. Don't sue me for their use.
This will not be a happy story. I'm warning you in advance. It may not be outright dark, but it definitely isn't light and fluffy.
Dawn trusted her younger sister. She always had. Buffy might not be the most mature of people - in fact, she might even be called shallow - but Dawn still trusted her. She'd always had a close relationship with Buffy, and that didn't change when Dawn went to study at UCLA.
So, when Buffy told Dawn that she had been chosen to be a Vampire Slayer, Dawn believed her. Even though it sounded like something right out of a fantasy TV show. It helped that Buffy was able to demonstrate a strength far greater than her petite form should've been able to wield.
Neither Hank nor Joyce believed Buffy. They thought she was joking when she told them. So Buffy gave up, resigned herself to their scepticism and stopped trying to convince them.
Dawn wasn't jealous of Buffy. Not after she burned down the gym. Not after Merrick died. But she did wonder about herself. She was the sister of the Slayer, after all. That had to count for something, didn't it?
Dawn was a brilliant student. She had always enjoyed school, had passed with flying colours, been accepted to UCLA with a full scholarship. It wasn't until one of her tutors mentioned in passing that Dawn picked things up as though she already knew them that she began to think.
Dawn was majoring in Physics. It was the only subject that had even been a remote challenge to her. Everything else was easy. Dawn had never wondered why - she had always assumed she was just naturally gifted. But the combination of a throwaway comment and her dwelling on the fact that she was the Slayer's sister made Dawn wonder.
So Dawn began studying things she had never even considered before. To her astonishment, she became fluent in Latin and Ancient Greek within six weeks. So she diversified, ranging into ever more exotic languages - which she learned at an equally fast rate. Her tutors said that it wasn't so much that Dawn learnt a language as that she merely remembered it.
It was around that time that her dreams started. Dawn began having vivid dreams, more lucid than any she had ever had before. Dreams of monks, chanting. Dreams of fantastical religious rituals, all centred on a glowing ball of energy.
For some reason, Dawn identified herself with that ball.
Dawn started to study history, a subject which had never before interested her in slightest. Surprisingly, Dawn found that certain time periods in certain countries seemed intimately familiar to her. Not on a mental level, but an emotional one. She couldn't explain why.
But Dawn did find that the historical periods that were most familiar just happened to speak the languages that she had learned so easily. On a whim, Dawn tried to learn a language spoken elsewhere in the world during that time period.
It was tough going. Dawn could have learned it, given time, especially given its similarity to the several other languages she now spoke, but certainly not in a matter of weeks.
Dawn didn't understand how such a thing could be possible, but she wasn't the sort of woman to leave things alone. She kept worrying away at it, trying to come up with theories.
Dawn had only one. Past lives. All she could think of was that she must have previously lived during those time periods and spoken those languages. But Dawn couldn't explain why everything was bleeding through now, why these things seemed so familiar.
It didn't occur to Dawn that the reason she was realizing all of this was because she was actively searching for ways that she was different. If she hadn't, Dawn might well have carried on thinking that she was merely a gifted student. She certainly never would've thought that she was just remembering things that she already knew.
It was shortly after this idea that Dawn had her dream. At first, it was no different than any of the others she had had - it was still populated with hooded monks and ominous chants.
Then, a note of panic threaded its way into the dream. The monks were no longer ordered, but clearly terrified of something that was coming. The Abomination, they called it. Dawn, in her dream, didn't think anything of that. In these curiously lucid dreams, she never did. She always felt like a spectator, just watching but passing no judgement on what she saw. It wasn't until she woke up that she ever thought about it.
So, in the dream, Dawn didn't think it was odd that the monks were talking about sending the Key to the Slayer for protection. It wasn't until she woke up that she put it all together.
Buffy was the Slayer.
The Key had been around for millennia. No doubt the monks that always seemed to surround it had spoken various different languages (their native tongues, most likely) and would've been abreast with current affairs in their own countries. So, in all probability, the Key would've been too.
The Key had been sent to the Slayer.
Dawn knew things about events that were impossible for someone her age to know - for anyone to know, in fact, unless they'd lived through them. As the Key had.
The Key that had been sent to the Slayer. To Buffy. Her sister. The person who she had always trusted, always been close to, closer to than anyone else.
Therefore, Dawn was the Key.
Naturally, Dawn told Buffy all of this. She was the only person Dawn could tell.
Buffy knew that she was the Slayer, and strangeness followed her around, but this was too much. Buffy thought Dawn was crazy.
Dawn thought that Buffy was probably right. This was crazy above and beyond having a sister who killed vampires. Nevertheless, Dawn still thought it was true.
It was impossible for Dawn to reconcile those two thoughts.
So Dawn checked herself into a psychiatric hospital. Maybe they could help her there.
Maybe they could convince her that she existed.