This is a weird book if you haven't read the author's other series in this setting. (The Hunter and Sun Sword series, not the Cast In ones.) And I haven't. You're cruising along with Jewel and her gang, trying to figure out what to do with their lives beyond starving in a gutter, having painful conversations (or silences) about responsibility and privilege. Then wham a bunch of characters show up from another series. Demons, magical catastrophes, tormented souls wailing in the streets, a titanic battle between the gods (our erstwhile protagonists are not in attendance, as it's several miles above their pay grade). Demon-god is defeated, party invitations for all, more painful conversations.
I guess it's a tribute to how well the earlier books were constructed: they are completely solid as the story of a street waif. They don't depend at all on knowing the books already written about her future life. But those threads were always there, and they make up a large part of this book. But not all of it. I'm not uncomfortable with the balance, but I didn't expect it either. Anyhow, I am now interested in reading the other serieses, so it's a win from the author's point of view.