- Droessen: the clocksmith who creates the nutcracker for Clara.
- The nutcracker: a present that Droessen uses to spy on Clara; he later strives to become his own real person.
- Clara Zelverhaus: a merchant's daughter, who Droessen plans to use to become rich.
- The Rat King: a sugar mouse who became real. Though Clara used him as an enemy for the nutcracker, the Rat King guides him towards becoming real.
- Frederik Zelverhaus: Clara's older brother.
- Althea Zelverhaus: Clara and Frederik's mother.
- The story is inspired by The Nutcracker and Leigh Bardugo's experiences as a child. After reading The Velveteen Rabbit, she was distressed by the idea that "only love can make you real."
- The Language of Thorns, Author's Note