"Once we were very different — our psyches constantly at war — [so] we struck a bargain, a spiritual compromise. We would grow more like each other, there would be a balance, but a bargain with a demon is no bargain at all. Demons cheat; it is their nature. Oh yes, I have grown more like Etrigan, and he… he too has grown more like Etrigan."
January 1, 1970
https://en.wikiquote.org/wiki/Alan_Moore