When she heard Paige's voice she knew she wasn't going to have to worry, Piper would be okay, because Paige could get them out of there. She had ignored her sisters warnings, because Billie didn't think her sister would ever hurt her to get to Piper. Or at least, she really hoped she wouldn't. She met her sisters Glare with a level gaze of her own, refusing to let her get past to get closer to the other sisters.
What Christy said next caused her jaw to drop. That had gone past hating Piper for a reason, to just being...a bitch. She knew Christy could be mean, but she hadn't expected that. "She's younger." Billie informed Paige, glancing over her shoulder for just a second. Her voice was slightly breathless, as if she could hardly believe what Christy had just said. "She doesn't know you. Leo still has his powers." she had a vague idea of the time she could be from, but it still stretched over a period of a few years.
Billie turned back to Christy, her face not angry, but completely shocked and disappointed. Her voice had dropped to address only her, ignoring the other two for now. "How could you?" she asked, looking at her as if she didn't even recognize her. Honestly, Billie was half wondering if she did recognize her. She'd been doing so well. "This isn't even the Piper from our time, and even if it was, none of this was her fault." she had really been hoping that Christy was beginning to see that.
"She didn't kidnap you, she didn't separate us. She didn't do any of that to you. You're still holding onto their lessons, aren't you?" as she spoke, her eyes got bigger, round, as if she was realizing something horrible. "They used you, they used both of us because they wanted power, they didn't care what happened to us." she had to know that by now, she just...had to.