Bella is hanging out in a Jarvis - the familiar one - handwriting a nonaggression proposal-slash-bribe. Has to be handwritten. Damn fussy demons. At least it's okay for her to conjure rather than personally harvesting the weird ink she's supposed to use.
"Think of the wishes as magical computer programs," Bella says. "If I wish 'unstick Glory from Ben, put Glory on Mercury', then this will either work or not, but if it works, something I haven't thought of could cause something I don't expect, just like computers don't always behave even though no one expressly programmed in any bugs. That's why I have to think of all the things that might go wrong first. What will Glory be able to do when she's unstuck? How fast will she be able to do it - faster than I can stop her? Are you, in some way you have not chosen to tell me about, attached to her in such a way that you will come to harm in her absence if I don't specifically wish around it? I know some people whose lives are dependent on external souls that are shaped like animals, it would not be the weirdest thing I've heard if your life is in some way dependent on Glory's occupancy and I can probably work around it but I have to know how to be sure."
"And I'm telling you, I can potentially use anything you know about her at all in order to find out. I have other sources of information too, I just need to know what to look for."
"I have a research guy who's investigating assorted books. I can spy on the past, if I know when and where I want to look. I have a crystal ball, but I have to interpret what it shows me in light of whatever I already know. I can wish up other information-gathering abilities if I know what sorts of things I need to find out."
"Okay," she sighs, since this is not a lie. "In the meantime - I can precipitate shifts between you and her, I did this most recent one. Would you expect anything bad to happen if I pushed you out front more often?"
"You don't think it'd make her hungrier for human brains, more pissed off, anything like that?"
"Okay. I guess I'll take you back where I got you now, then, unless there's anything else you'd like to tell me."
"Here we go. I guess I'll see you when I work out a plan or she's about to hurt someone and I have to go with whatever I've got at the time, huh?"
She heads back to Canada, although she half-suspects Sherlock will have teleported Soph to a more habitable climate by now.
"So, I can poke the hellgod into turning into her mortal host with a pentagon, the mortal host doesn't trust me and doesn't know much, I've got Giles looking up Glory and - relevant topics, and I'm going to check on Glory-or-Ben every few minutes so I can intercept if she's about to eat somebody else."