I was right, and this was Lash route choice for Harry's dating sim life.
So, my argument for why we need to make Lash a body, and make it as strong as possible and as quickly as possible:
1) We know that she's a creature of darkness, and we know that she's metaphysically as powerful / strong as
ancient vampires, Maeljin Incarnae, Yama
Kings, Malfeans, the greatest of Black Spiral Dancer
heroes, other Exalted, and the like. Jaggling or Gaf-
fling-level Banes and all fomori are always lesser beings.
So, she's an incarna-level (WoD classification) spirit. That's the same grade as naagloshii. This means that a) she can't be bound by ancient sorcery binding we have, and b) she's likely noticeable
2) We don't know how far senses of the Fallen extend, but it's fairly likely that if Harry comes back home, Lasciel will notice that he isn't bound to Lash anymore. If he brings Lash back with him, Lasciel would also know, even if she doesn't now. There is, however, a non-zero chance that if Lash doesn't come back to Harry's apartment, Lasciel would assume, at least for a time, that we destroyed Lash while freeing Harry. That's still alarming, but far less dangerous to Lasciel and all of Denarians in general than Lash free and rebelling against her.
3) Following from point 2, we, that is Molly and Exalted, seem to have one advantage over most of the setting - we are operating on a righter time scale. Plans and counter plans of the forces of Dresden verse are usually a thing of months and years. We are operating on the scale of days to months to enact global change. This gives us an advantage here - people, from denarians to Black Council, will be after Lash as soon as they know about her. Given that Anduriel is a thing, it's very likely that Harry is under shadow surveliance if not constantly, then at least from time to time, and same with us. Lash's existence will be discovered soon, if it hasn't been discovered already. There will be people trying to destroy or steal her. And certainly there will be people trying to prevent her from getting power and her own body. This means that the sooner we make said body, the better. And this body would need to be able to defend itself against... well, denarians at least.
4) I assume that we'll be making the body in our kingdom, or using resources of our kingdom. In two weeks time, Council's best diplomats (read "spies") will be sent into our kingdom. If we are doing a major working involving uprooting celestial order, it's better to do so now, before we have eyes watching and ears listening. It provides at least some manner of secrecy and surprise.
5) AP-management. We have 6 points + 2 for furthering the projects we do with those 6. This month we don't have anything directly looming over our head. White Court minor talent genocide plot has been disarmed, naagloshii has been driven away, Red court is unlikely to be react within a month, White Council infiltrators still don't know we know about them. We are in AP hell near-permanently. This is one of the few months in the quest where there is a bit of a lull and we are free to be proactive, instead of dousing fires all around us.
6) The longer Lash has a body, the more time she has to acclimate to it. And whatever comes with it (like, I wouldn't be surprised if she was chosen by fidellachus as a knight of the cross).
7) Harry, as any true noir detective should, gets a secretary. Or we get a new circle mate. Because yeah, she's not going free exactly. Lash in a 5+ dot body is a being that could probably keep up with at least Lydia, if not Molly (for a certain amount of time).
