In An Absent Dream by Seanan McGuire (Wayward Children, #4)
There's a strange calm in already knowing how a story ends. In An Absent Dream is filled with sadness and wonder, too-clever bargains and barely-survived scrapes. Lessons of friendship, loss, fair value, and the weight of promises. Welcome to the Goblin Market.
This focuses on someone whom we met earlier in the series as far as the reader is concerned, but in her own timeline she is barely getting started. This creates a sense of tragedy and wonder all tangled together as we slowly learn the reason for the bargain waiting in the end of the story. The pacing is very well handled, skipping what would only bog the story down, lingering on her indecision just enough to make the reader understand what would drive here to her eventual choice. I love Moon's wildness contrasting Lundy's steady attention and determination.
The story is great, I like this version of the Goblin Market and it has the nebulous mix of rules and capriciousness that makes the setting feel otherworldly, which is perfect for this series. There was a moment partway through where I was torn between rooting for success and failure because both options seemed to have a terrible cost. The slow unfolding of rules helped convey how much Lundy was growing up, it helps to keep the reader from getting an info-dump while still making sure the character knows what she ought.
CW for body horror, child death (not depicted), pregnancy (brief mention).