Who is Shaney from the novel, The Only Good Indians?

Shaney is a Crow Native American woman. She is a vessel for the elk spirit, although it is ambiguous whether the elk spirit is inhabiting her, possessing her, or has killed the real Shaney and shape-shifted to take her place. Shaney works at the same post office as Lewis. She is flirtatious towards Lewis. Lewis never has physical intimacy with Shaney, but he does develop some emotional intimacy with her. However, he eventually suspects that she is the elk spirit, so he kills her. Local vigilantes then kill Lewis, and the elk spirit merely reincarnates.