"Based on your deep personal regard for them? Because you have kidnapped their great-grand-niece? Because magic lie detection?" asks Bella.
"I am just very, very good at predicting people," says Libby. "If I know someone well enough, I always know whether or not they are lying, and usually why. This person wasn't."
"I'm not particularly talented at predicting people. So instead, I read Whistle's mind. With her permission and magic of her manufacture; she wouldn't want me to be nervous about what she gets up to and she's happy to render that unnecessary."
"I mean, in what ways besides curbing her destructive impulses and letting you read her mind does she make your life easier?"
"It's nice to have a collaborator for magical experiments," Bella says. This seems like harmless, obvious information.
"And, of course, before I watched Bridget get shot, Whistle was the only person I could really talk to about magic."
"Yes. I take it she really wasn't keeping you posted on our activities? We got followed by a creep, we told him to piss off, he turned out to have a gun and he managed to put a bullet - well, not in, on her before I took him down. I know aikido," Bella adds.
"Why, did you think she was? No. Although I did ask her if you were dead, right after you dropped off the map."
"I asked her all the questions under the sun, but I can't take anyone's word as gospel, and Whistle's the only person I can check up on directly."
"I sometimes exhibit discretion, but at the time I had no reason to restrain myself around Bridget."