That curse is what turned her into a gorgon, a snake-headed creature with the ability to turn people to stone with a look, in the first place. She can’t pass herself onward or enjoy the temporary relief from past memories which comes with that process, meaning she has been the same person in the same body since she was cursed by Athena back in ancient Greece. Unlike the Idols, who can pass a piece of their soul onto another person when they die, granting them a weird form of immortality that includes a short period of memory loss of their various past lives, Medusa is just an immortal being in the traditional sense. While most of these are entities that were once worshipped as gods, like Apollo and Athena, others are humanoid creatures of legend, like the Minotaur Asterion, and the gorgon Medusa.
With a week to prove her innocence in the face of total annihilation, Grace tracks down and talks with several other immortal beings that are also in the modern world with her.
The player character, Grace, inherits the soul of a murdered Muse (yes, that kind of Muse) and winds up on trial for the crime. Stray Gods: The Roleplaying Musical is pretty much exactly what the title implies. Note: This article contains spoilers for Stray Gods, as well as discussions of sexual assault.