Names And Dates And Times
It starts with curiosity.
She's begun to understand Giles's habits, his patterns of living: she knows that when she comes in at two, he'll be stirring cream into his coffee, and if she pokes her head into the library before ten he'll just point irritably towards the center of the floor, her cue to begin the sets of kicks and punches he's walked her through.
They are still learning each other, a new Slayer with her Watcher, but even after a month in Sunnydale she's noticed how easily they fell into their roles. They bicker, but it's mostly good-natured. He knows what he can put her through, what her limits are, and how to push them. She spends more time with him than she has any one person, and while seeing Xander and Willow are the highlight of her day, she's growing used to their routine.
That's when she notices the books. There are books everywhere, occult encyclopedias and roughly translated volumes of prophecies and almanacs, with the rare literary novel mixed in. But she's seen the books Giles is most engrossed in, and they're all of the same nature: small, brown, hand-bound. A date imprinted on the top, from year to year. There's always a different one, unless one volume is especially thick, and more than once she has to bang something loudly on the circulation desk to draw his attention from the worn pages.
She goes to the library one day, at an hour she knows he will be out, and finds one of the books lying under files loosely stacked on Giles's desk. She takes the book in her hands, feeling its weight and gently rifling the pages with her fingers. The cover reads 1587-1604 and when she's reading she realizes this is something she vaguely knows from history, but it's even more important that this is part of her past. Her lineage.
She doesn't notice when Giles walks in, when he sees her and what she is reading. He stands, visibly frustrated, and cleans his glasses. For a moment he seems stuck in indecision, but he finally leaves, and Buffy lifts her head, thinking she's heard something when the soft brush of the swinging door settles.
Later, she carefully places the book where she found it, and when she walks home her head is filled with the words of another Watcher about another Slayer. She feels desperately lonely, though it's paired with the realization that she is perhaps less alone than she has ever been in her life. Buffy is finally starting to realize what being the Slayer means, and suddenly she runs, flying down the sidewalks and through the graveyards, cutting through the forest and reaching the bluff where people come to make out and have sex. She looks over Sunnydale and understands the concept of duty, and it is the tales of other Slayers that make her feel whole.
The next day, she comes into the library at two and Giles is stirring cream into his coffee. On the table there are stacks and stacks of small brown volumes, and he motions for her to sit down and starts to explain just where she came from.