'Medraut,' I murmured, 'Do not call me Jocasta, or I will let you borrow my brooches...'
Have this story (published in "Sirens and Other Daemon Lovers," available as an ebook) on hand immediately after reading The Winter Prince (which I highly recommend you do!). Told from the point of view of the antagonist Morgause, it fills in some of the protagonist Medraut's backstory, which is darkly hinted at in the book. It shares an amazing atmosphere with the book which isn't apparent in the sequels: It's full of tension, self-destructive pride, defiance, messed-up family relationships, cruelty, and loneliness.
His lips curled back, barely, and he croaked at me, 'I do not need your brooches.'
"'Can you even love?'
'Yes. Yes. All the wrong things. The hunt, and darkness, and winter, and you, Godmother.'"
This is a book I wish I had written.
It is a first novel, and cool and sharp and glittering, like a heavy, hanging icicle. It is very dark, with just enough hints of the backstory to let you fill the rest in for yourself.
It is an Arthurian retelling, focused on Mordred, in a version in which Arthur has legitimate heirs.
The narrator, Medraut, is complicated and brave and oh-so-fallible, like his siblings and father, the other central characters. He addresses his narration to his mother-and-aunt Morgause, who is terrifying- sadistic and false and capable of cutting to the bone.
The ending departed slightly from the subtlety of the rest of the book, spelling out the epiphany, but that's a minor complaint. The voice is intense, deliberate, engrossing.
The Winter Prince is a short read, just over 200 pages, and a brilliant one. There are sequels, but they branch out further from the Arthurian setting and don't seem as good. This one stands alone, and is a masterpiece.