Girls of Paper and Fire by Natasha Ngan
This was a magnificent world the author built around castes from humans (the lowest) up to demons (the highest). The cast surrounds the concubines serving the Demon King and it's profoundly inspiring. I adored that our lead, was not all powerful, all knowing, or magical in mysterious ways. She was an ordinary girl fighting hard to survive, dealing with trauma, and finding love in strange places along the way.
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