Swirsky wrote one of my favorite things that I read for the last Hugos, and I think she's outdone herself this year.
The titular “Lady” lives in a brutal fantasy world. Her own Land of Flowered Hills is matriarchal with an underclass of women, the "brood," who serve as surrogates so that the female leaders aren’t exposed to the vulnerabilities of pregnancy. The Lady herself is a powerful sorceress and lover to the Queen, but she is felled by betrayal early in the story. This in itself would make an intriguing little short, but the story only picks up from there. The Lady becomes one of the "Sleepless Ones," powerful spirits that can be summoned for consultation through deadly magics. We see several summonings from her perspective over millenia, and we witness the evolution and changes in The Land of Flowered Hills and the kingdoms, increasingly patriarchal, that succeed it. There’s a very nice vignette along the way about a man who shares his body with the Lady in a summoning as he tries to save his people from a volcano, and a great extended portion where we see a more civilized and "modern" magical kingdom, before we get a fittingly epic ending to the millennia long story.
Each of these timeframes and the characters within them are wonderfully evoked by Swirsky, and each left me wanting more without feeling unfinished. There are lots of great little details, including the later society misrepresenting "sleepless ones" as "Insomniacs," that sparkle and add to the richness. And, there is a strong emotional core. The Lady is from a hard world, and she can be cruel, but she is also sympathetic, as are many of the people she helps and/or betrays. Swirsky is a true humanist, and she melds world-building, character, and emotion (all with simple, elegant prose) in a way that is everything I look for in short fiction. She reminds me a lot of Ted Chiang, who I think she outshined this year.