And here's the final chapter of this story.
The lunchtime bell rang, and Buffy got up from her desk and stretched. As soon as they'd left the library for their first class Willow and Xander had besieged her with questions - "What's it like?" "Is it weird?" "Is she really you?" And she'd tried to answer, but there were some things that just couldn't be put into words. The sight of herself, strong and confident and adult, had touched something deep inside her. It was her future, and... and it didn't suck. She had something to look forward to, to be proud of. She held the knowledge warm and close in her heart, and it cheered her as they retraced their steps to the library.
Where she found her future self looking utterly frazzled and fed up, surrounded by a litter of open books and discarded coffee cups. She groaned theatrically as she saw them coming in.
"I'd forgotten how much I hate research!"
Buffy grinned. "How could you forget that? Isn't it, like, central to the core of my - our - entire being?"
"Yeah, but in the future I've got an entire team of people to do my research for me. I've forgotten what it's like to have to do it myself."
"Seriously? And do you have a private army of evil-fighters too? And fancy gadgets and a secret base in a castle somewhere?"
"Hee! Why, er, no. Nothing at all like that, honest."
"Oh. If you've g-got lots of people to do research d-does that mean you don't need us in the future any more?"
"Don't be silly, Will. I wouldn't be here if it wasn't for you. In, er, more ways than one, but never mind that now. You're indispensable. Both of you."
"I'm indispensable guy? Really?"
At that point, Giles walked back in carrying a pile of books. "If you're so indispensable, you can help me carry more items up from the stacks. Here's the list; come on."
Buffy, Willow and the other Buffy shared a grin as a reluctant Xander trailed out again. But Buffy's grin faded as Giles poked his head back out through the door. "You too, Buffy. It's a long list. Willow, perhaps you could make a start on Grigorax's Codex?"
Buffy pouted, and flounced out, leaving her future self with Willow. By the time she got back they were deep in conversation, and she overheard the last snatches of their talk. It was so fascinating she paused a moment to listen.
"That's so romantic! But what about- about me? I know you can't tell me in detail, 'cause of the future-changing and poofing factor, but some hints, maybe? Does Xander ever finally notice, uh..."
"Oh, Will. Are you sure it's really him you're in love with?"
"Who else would it be?"
"I don't know... but are you, um, sure you're not, er, crushing on him because you're trying to hide your feelings for, uh, someone else? Maybe someone you, er, don't want to admit even to yourself that you like?"
"Like who? Xander's the only boy I've ever felt this way about!"
The other Buffy blushed. "That's kind of my point."
Willow seemed to hesitate; but then the familiar look of stubbornness came over her face. "I love Xander."
Future!Buffy sighed. "If you say so. Just remember, Will, I'm your best friend. You can tell me anything, I won't be upset or shocked. Well, maybe a little shocked but I'll get over it. Just like you will a few years later when you find out about Sa-... um, anyway. Oh look! Twentieth Century Buffy is back! With books!"
Before long the five of them (or did it still count as four, since two of them were the same?) were sat around the table deep in study. Xander had brought sandwiches from the cafeteria to tide them over, and there was no sound except for munching and the rustle of pages.
So everybody jumped when Giles thumped his book down and said "Oh, of course!"
"Giles! Can't your sudden inspiration be less sudden and more inspirational?"
"It's the Hellmouth! When the time portal was opening, the end of it was drawn towards the other portal - the one here in Sunnydale. It's the strongest source of mystical energy on the continent, and it simply drew Buffy in towards it."
"Like a giant magnet in a cartoon, except she didn't leave all her clothes behind, unfortunately?"
Buffy scowled at Xander on her counterpart's behalf, since she seemed to be concentrating too hard on Giles's explanation to be distracted. "What sort of cartoons do you watch?"
"But why in 1997? Why not later, or earlier?"
"I don't know. Perhaps it's something the Master has done? When he tried to escape during the Harvest, perhaps the mystical energy he gathered made the Hellmouth stronger somehow? But that still means... oh, no, wait a moment..."
He studied the book again, and Buffy met her future self's eyes and grinned. "Told you he'd work it out."
"Got it. When you came back from 2298, the portal latched onto the strongest source of mystical energy in the area. And that means temporal area as well as geographical. If you move a shorter distance, eight years rather than several hundred, the margin of error will be the same proportionately, which means far smaller in absolute terms. I believe physical proximity exerts a stronger influence than temporal, however."
"And again in English?"
"You can go back to 2005 and you won't get pulled away back to the Hellmouth here again in this year. You might, however, get pulled by the version of the Hellmouth that exists in 2005. You'd still be in your own time, but you might end up in Sunnydale again rather than New York."
"You know, that's really not going to be a problem. Trust me."
"So, I suppose our time together is drawing to a close. It's really been the most remarkable experience meeting you, I--"
"Hold on a minute." All eyes turned to Willow, whose face was drawn into a scowl of concentration. "How come Buffy didn't know this already?"
"'Cause I'm not a time-travel whiz. We can't all be geniuses."
"No, I mean, why don't you remember us having this conversation? I mean, you've already lived through this, so you ought to remember yourself coming back in time and everything."
"Oh, I see. Well, I don't remember it, but why does it matter?"
"Actually, Buffy, I think Willow has something. This could be serious. Why don't you remember? It must mean that the you from the future is not the same as the you that's here now. The future has diverged; you remember different pasts. Oh my."
"Giles, I didn't understand a word of that but it sounds bad."
"It means I'm about to go *poof*, doesn't it?"
"Or that when you get back to your own time everybody else has gone *poof*. Or, or maybe there'll be intelligent apes ruling the world and keeping humans as pets..."
Future!Buffy cringed. "I hated that movie."
"Oh, this is bad."
"Wait a minute!" Everyone turned to look at Xander. "You said Buffy doesn't remember this happening? Well, rather than some sinister time-travel paradox thing, maybe she just forgot about it? I forget things all the time."
"I hardly think I'll forget this." But then Buffy saw her counterpart frowning, and a light dawn slowly in her eyes. Then to her confusion, future!Buffy gazed up to heaven and mouthed the words "I'm sorry" before turning back to the others.
"You will forget it. It's the only way it could have happened. By magic. One of you must cast a forget spell on you all, so you don't remember me being here. So I don't remember this happening in my past."
"Good lord. Is that even possible?"
"I-I don't like it, Buffy. It sounds really dangerous. And also creepy, wiping our memories like that."
"I'm sorry, Will, I really am. More than you'll ever remember. But the spell is possible, and it works. You just have to be careful to judge it so you only erase the memories you want to lose, instead of all of them. But you can do it."
"M-me? But shouldn't Giles...?"
"You've done it before... er. you'll do it again. You're good at this, believe me. Scarily good. A natural talent. Just, uh, be careful, okay? Don't let it go to your head, or much badness will ensue."
"I'll be careful. I promise."
Meanwhile, Giles had been thumbing through Krause's Compendium, and found what he was looking for. "Aha! Yes, Buffy, you're right. Remarkable. We'll need some supplies though, some herbs. I wonder if I have the right materials in stock? I won't be a moment."
As he left, Buffy slumped down on the edge of the table, feeling sulky. "So we'll forget you came? All that stuff you carefully didn't tell us, we'll just forget? It's not fair."
"I'm sorry. But maybe, the important stuff, you'll keep in your subconscious? I mean, I've certainly had my share of déjà vu moments. Maybe I did remember some of this. The stuff about believing in myself. Being strong."
Giles bustled back in, a curiously non-descript pink flowery spring of greenery in his hand. "Got it! So, I suppose we'd better begin."
"Okay. Except, one thing first. You don't suppose you could lend me enough money for a plane ticket to New York, could you? My credit card has a slight problem, in that it was issued in 2002... I promise I'll pay you back in the future."
"But if I don't remember lending you the money, how will I know to ask for it back?"
"You can trust me, can't you? Pleeease?"
Giles sighed. "That sort of wheedling is far more becoming in a teenager than an adult, you know. But very well."
And so it was arranged.
Buffy Summers, 24-year old leader of the Slayer Army and saviour of the world a whole lot of times, peeped through the glass window of the library door as her impossibly younger self and her friends gathered in a circle. She watched as Willow held the Lethe's Bramble on the palm of her hand, and said the words of the spell. She saw the shimmery glow pass through the herb, and watched the four of them stagger back in confusion. Giles had left a note propped on the table giving a carefully edited explanation of the magic, just in case it went wrong, but it didn't seem to be necessary. They were soon talking and chatting happily enough, going about their lives.
Time to leave, before they saw her and the whole process had to start again. She felt hesitant about going: back to the complexities and loneliness of the real world. But she had responsibilities to live up to, and there were compensations. She had friends and family in the future, too, even if they were... different.
But not that different. She smiled at her own thoughts, and turned her back, and walked out of Sunnydale High School for the last time without a backwards glance.