Poppy is the novel’s protagonist and narrator, and all major literary elements develop around her perspective. She is Casteel Da’Neer’s wife and unofficial heartmate, and the relationship between these characters develops an otherwise epic fantasy into a romance novel. Poppy’s appearance undergoes several changes in The Crown of Gilded Bones. Her eyes, once green, become increasingly silver as her magical powers develop. While her thick, red hair remains the same, the scars that cover her face and body begin to fade. She is only 19 years old, while Cas, her husband, is over 200 years old. Poppy has experienced “The Culling,” a magical puberty during which her gods-given magical abilities develop and strengthen. During this time, Poppy gains control of the wolven and draken, two powerful shapeshifting species that are loyal to Atlantia.

Although Poppy initially believed that Coralena and Leopold Balfour were her biological parents, she eventually learns that Queen Ileana (Isbeth) is her mother. She also learns that her father is Ires (the twin brother of Malec and the son of Nyktos, a Primal God). This parentage means that Poppy is a goddess, though the strength of her power remains unknown at the novel’s close.