She had no idea what the world around her is like. Completely in bliss of the dangers around her. And Buffy never told her. She took it upon yourself to protect her from the big bad monsters that exist. Slaying demons when she wasn't looking, and kissing her fears away when she was. Danielle, she had said her name was. Such a pretty girl she had been. They had met at a school football game, and that was it. She had been head-over-heals in love.

But then Buffy moved away, and met Angel. From the few letters Buffy had received, she knew Danielle had met a boy, too. And then another, dumping the first. Because popular girls could do that and get away with it. So they had moved on, and a year after Buffy had arrived in Sunnydale, they lost contact. Danielle moved with no forwarding address, and that was it.

So it's fair to say that when she saw her clearly outside the Bronze, clearly recognizing Buffy, slaying a vampire and introducing herself as Faith, it was a shock.