In a fantasy world where magic exists alongside familiar forms of scholarship, a mysterious event wipes out at least one city and possibly most of the human world. Rukha, a geographer, is exploring an abandoned tower when Eshu, a student wizard, emerges from the "Mirrorlands" that used to connect major cities via a parallel world and literally runs into her. Rukha decides they're friends and it's her job to help him get home, but with modern forms of transportation disrupted, it turns out to be a longer journey than anticipated as they make their way across the post-apocalyptic landscape.
The good: worldbuilding. Creepy ruins of a city that's been overrun by crystals:
All around him, towering spires of fluorite and fool's gold clawed toward the sky. Downhill, where switchback streets led inexorably to the sea, shards of quartz gleamed like knives from every roof and balcony. Blood-brown garnets lay beneath the ruins of merchants' awnings, which hung in shreds over heaps of broken stones. Temples wept icicles of some thick, green stone swirled with black.
Whatever this city had been before, now it was a wasteland of glittering rock.
Eshu's branch of magic involves "telling the world a story" and convincing it to work differently; this is usually expressed through the metaphors of song, with evocative imagery. When fighting another wizard, he tries to make a magical airship fly, and she tries to make it sink:
She didn't sing, but he felt her magic like a song: the remorseless pull of gravity. The eager ground to which everyone in time returned. The laws of the universe, every fixed planet orbiting every spiraling star, all of them circling the vast devouring void. All obeyed a commandment older than language, older than life. It was right. It was righteous. The first thing any creature did was fall.
Usamkartha, one of Eshu's wizard friends, passes through a mirror as it's breaking, and the description is compelling:
When she looked at him straight on, he was an ordinary man of her mother's generation: lean-faced, dolorous of eye, his hair greying and balding. The veins stood out like serpents on the backs of his hands.
When she let her mind wander for even a moment, he was a mass of shining scales and coils.
"What happened to you?" she asked quietly.
With his free hand, Usamkartha thumped his book. "I am writing a manuscript on my condition, if you care to know the details," he said. "The first true theoretical work on the aftereffects of traveling through a broken mirror--the condition has been called fragmentation by past scholars, but I believe it is more properly termed abstraction. If I'm going to die from this, at least my death advances the field of scholarship."
This description of Eshu practicing his faith in a minority environment is also great:
Being Njowa had mattered so much to him back in Usbaran, when he and Mnoro had been the only Njowa at the university; they'd kept the feasts and fasts together, knelt for prayers together, warned each other about which street vendors fried their vegetables in pork or duck fat. When their exam period meant they couldn't make it home for High Summer, they'd built a holiday hut out of blankets instead of reeds and hidden in its shelter, trading city comedies. Faith had been a kite string linking him home--to Kondala, to his family, to the centuries of far travelers who had come before him.
The bad: I didn't really care about the characters. Basically Rukha just decides "okay, we're stuck together" and never reconsiders, even when Eshu is being whiney and frustrated that he can't find any hair cream or lotion in the post-apocalyptic world. She's been out of university for "a few years"--if there were a big age difference, I could maybe see her being protective in "he's just a kid trying to get home to his family" kind of way, even if Eshu thinks of himself as an adult. But it just kind of borders on the therapy-speak ("you're really not treating me like a friend right now," Eshu confronting his abusive ex), in an underwhelming way. I get that it's trying to subvert the "mismatched strangers to friends to lovers" plotline in a "mismatched strangers to friends who are very important people in each other's lives, they don't need or want a romantic or sexual aspect to their relationship," but there are plenty of times when it's like "why are these people even hanging out together if they don't particularly like each other."
Most of the back half of the book is set in the city of Kulmeni, which is less catastrophically impacted than other human settlements. After "the change," a new "prince" took power, who was until recently the leader of an organized crime gang. The complexity of "maybe she's actually making things better for the common people and representing them better than the aristocracy, maybe she's just out for power" was handled well. There's a great interchange where Eshu talks to the Anjali River, who sometimes appears in a deity form, before they have to duel (it makes more sense in context) and points out the parallels between his situation with an abusive ex and the city's situation with "do we just stick with the devil we know?" and that helped, somewhat, in justifying the "abusive ex" plotline.
There's a brief mention towards the end of the book about Njo, the deity Eshu worships, that made me hope for more "Steerswoman" parallels with the combination of magic and science, but that might have been just wishful thinking on my end.
Bingo: Impossible Places (borderline hard mode, if you count all the chapters set in Kulmeni and/or the Mirrorlands I think it would be over 50%?), Gods and Pantheons (the Anjali's anthropomorphic form is referred to as a god), LGBTQIA protagonist, was a previous Readalong, maybe Stranger in a Strange Land?