I don't know if there is previously established canon for what sort of powers one would gain by becoming a devil, but I found Hill's depiction of Ig's new-found abilities fascinating. As people begin to tell him their most evil desires and he can see their past sins with a touch, the reader is given a view into things often left unseen and unsaid, and Ig is given a chance to discover in these secrets the truth of his murdered beloved. His search is at once frighteningly dark, and tender and sweet.