Giles was stumped. There was no accounting for both thier memories being faulty. He struggled to put forward a theory.
"I just put a down payment on the magic store, Xander and Buffy helped me cleanup... and Dawn kept annoying us all until..." he realized the name Dawn drew more confused faces. "This is getting tiresome. Some how were all expierencing some sort of time or memory shift.... but which is it?"
"It... could be a spell. There are various memory spells that could-"
It dawned him all at once. What if his memory was gone as well. There was almost no way to know.
"The two of you were, in point of fact, dating. Now, im no expert in human sexuality, but frankly the romantic side of this needs to be put aside for a moment while we figure this out."
"If it isnt a memory spell, than this could be far more dangerous than just some short term slip up. We could be dealing someone tampering with whole dimensions...or even time itself.... who would be foolish enough to...?"
"Willow, we need to find Buffy. If this is a memory spell and its affecting more than just the two of you, the whole city could be in danger." The danger from such an event was immense. He retreated to a nearby bookshelf, picked a book labeled the Magic of Time & Space, and turned several pages stopping when he found a short list of items. Moving quickly he jotted down several of the items on a scratch pad.
"Tara, head to the magic shop and gather up these supplies. We need to do a Continuity spell, that will at least tell us if youve traveled forwards or ive traveled backwards."
"Meanwhile I'll be..."
He stopped to look at himself.
"-getting dressed, if im going to decipher cosmic time frames ill be damned if im doing it in my jammies." He said slightly embarrased.
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@Meliza
As dawn arrived at the magic box, she found Giles(S6) steeling himself at the entrance. He was wearing the outfit he had on when he'd faced Dark Willow years ago in the magic shop, in fact it looked identicial. He looked back at her and shook his head.
"Young Miss, you'd better go... theres something terrible happening in there." He paused almost recognizing her, but clearly focused on another task.
He said nothing more and charged in his hands aglow with magical energy, preparing to blast away at his former protege.
The magic shop door was ajar, with several shoppers hustling in and out. There seemed to be a small que inside, and behind the counter an older male clerk whose name tag read "Andrew" smiled broadly at Giles(S6) as he entered.
"Welcome to the Mr Andrew's Magic Box...I... Mr Giles!"
"Andrew? Where is Willow!?" Giles asked with a serious glare.
"Will? I... I don't know. Its been ages since Ive- say you dont look like youve aged or deaged a day!"
"What?"
"You're looking mighty spry for a guy who should be like 70."
We have to stop Willow. I came as soon as i could. With all her magical power she could..."
Will, dangerous... that was ages ago she would never-"
"Somethings happened... you werent this old when I left Sunnydale, somehow everythings...shifted. I dont sense Willows dark magics... but...how?"
"Whoa... slow down Mr G, your totally confused. Willow doesnt do the dark stuff anymore...at least she hasnt for like 20 years. I bought the magic store and you retired remember, something about time for someone else to take up the manticore?
"Mantle?"
"Whatever-"
"Now see here young man, im not that old, or senile, and if the world is so confused as to allow you to run a business... were in lot of trouble." Giles said omniously.