This is a promising debut - deeply character-driven, with multiple rotating POVs and an intricately-built pan-Asian/post-apocalyptic/semi-drowned world. I loved how many sea creatures exist among the Fathomfolk - kelpies, sea dragons, sirens, mermaids, and more - and how Chan is blending mythological inspiration and fairy tales (East Asian dragon lore meets The Little Mermaid makes for a great premise). 
I'm still grappling with a few of our characters, though, and their roles as the series progresses. Mira, in particular, half-folk and a border agent for the city, attempting to affect change from within, has me unsure of Chan's intention for the story and thoughts on resistance to violent systems. I'm interested to see where the series goes from here, as I really enjoyed the expansion of the world at the end, the potential directions the sequel can take, and the many possibilities that lie ahead for all of our characters. I am grateful to have multiple POVs, and probably enjoyed our sea witch's story the most. These are all flawed characters, grappling with their own insecurities and ambition as they question their loyalties to each other, and fantasy readers who particularly enjoy character work will appreciate this series start. 
Thank you to Netgalley and Orbit for an advanced reader's copy!