Ah, an apostate is someone who--turns their back on something, I believe? Or what they used to believe. It also refers to anyone who commits the crime of being magical outside of a Circle where mages are supposed to be.

( was he just a different kind of mage? she figures that what he means, even she and her own sister had different affinities for schools of magic. for right now anyway she's too bothered by a reality where all mages are killed on sight. it's the nightmare of her fanatical companion come true--and which she told him was impossible. it's hard not to be uncomfortable, so her sarcasm is more biting than she means. ) A crime, surely, for rats are actually guilty of carrying disease and being disgusting. What happened to make him so scared? Did he get spurned by the love of his life?