Anyhow, someone is challenging Miss Tyrant for control of Nameless City. She cannot allow this ("You don't care about my city the way I do," she tells her challenger, in the most unintentionally hilarious line of the month) and so she stomps into San Francisco looking for power-ups. This brings us to the second failure, which is that she has years and years of backstory, all of which we have to be told about, none of which is relevant to the book. We get not one page set in Nameless City (the ostensible driving force of the plot). We meet the protagonist's servant and get the paragraph precis of all the crap he's been through because of her. We learn about her Cursed Cloak of Ass-kicking (the Curse of which is, in practice, a mild headache for a few minutes after she uses it). We don't care about any of it. I imagine that Pratt has written all of these stories, and maybe they're even published somewhere, but in this novel they're concrete galoshes.
All that said, there is a lot of running around mystical underground San Francisco and kicking mystical ass. These scenes are not badly written. There are funny bits (intentional ones). It's possible to enjoy this book; it's just not possible to do it without wanting to yell at the author.
(* Actually, it has a name, but it's fictional and I can't remember it now.)