Authors:

I've since discovered that many human beings need no supernatural mentoring to commit acts of savagery; some people are devils in their own right, their telltale horns having grown inward to facilitate their disguise.

Dean Koontz (2016). “The Complete Odd Thomas 8-Book Bundle: Odd Thomas, Forever Odd, Brother Odd, Odd Hours, Odd Apocalypse, Odd Interlude, Deeply Odd, Saint Odd”, p.46, Bantam
I've since discovered that many human beings need no supernatural mentoring to commit acts of savagery; some people are devils in their own right, their telltale horns having grown inward to facilitate their disguise.