"Me too, what?" she asks, giving him a look. And that's a good question. Did she bring her boyfriend? "I guess so." If Peter's here, Charley probably is too, right? She hasn't really made it a habit of hanging out with Peter on her own. (For a while she wasn't sure whether to refer to him as Mr Vincent, but after they more or less became friends, or at least friendly, that seemed weirder, since Peter isn't exactly the image of maturity and authority.)

Maybe Charley organised a trip? Yeah, that seems reasonable. She's not lucid enough to realise that she should probably actually know this.