Medusa, the Gorgon daughter of sea gods Phorcys and Ceto and beloved sister to Sthenno and Euryale, is the protagonist of Stone Blind. She faces several antagonists in Poseidon, Athene, and Perseus. Unlike her immortal sisters, she is mortal and relatively weak. Arriving at Sthenno and Euryale’s cave as a baby, Medusa grows and changes, shocking her unchanging sisters. Although she is called a monster throughout the novel, she exhibits humanity through her actions. Cornered by Poseidon in Athene’s temple, Medusa chooses to be sexually assaulted to spare a mortal girl. During this ordeal, she explains her views on monstrosity and beauty, framing Poseidon as shallow. With her sisters’ support, she works through her trauma, only to be cursed by Athene for being assaulted in her temple. Medusa’s love of the sea and her hair transform into fear, though she grows accustomed to her petrifying gaze and snake hair.

The Medusa-Narrator is the severed head of Medusa, the novel’s first-person narrator. When Perseus kills Medusa, she retains consciousness and is gifted with knowledge beyond her scope. She laments her role in Ceto’s death and scorns Perseus and his mother, Danaë, but still finds compassion within herself to grant Athene consensual “death” through her gaze.