This essay explores how Rachel Hartman’s fantasy duology Seraphina (2012) and Shadow Scale (2015) functions as posthumanist young adult hagiography. As a hybrid—and especially as a hybrid between human and cold, rational dragon— Hartman’s protagonist Seraphina begs comparison to Donna Haraway’s cyborg, existing at the nexus of embodiment and discourse. Like Haraway’s cyborg, the figure of the half-dragon as constructed by Seraphina’s culture is associated with “blasphemy,” yet Hartman’s duology shows that a cyborg need not be areligious and can even be a Saint, as the half-dragons are ultimately revealed to be. Like the grotesque bodies of saints in Christian hagiography, the bodies of Hartman’s half-dragon Saints challenge the boundaries of the modern self, gesturing toward posthumanist intersubjectivity through the ways in which their minds and bodies are linked. However, the series also emphasizes that each half-dragon occupies a different set of intersectional subject positions. Through depicting Seraphina’s negotiation of an intersectional religious identity and her ultimate performance of saintly intersubjectivity, Hartman’s series suggests multiple possibilities for readers as they narrate and perform their own religious identities.