Alright, so let me get this all right. 

Most of humanity doesn't know about the demons, portals and all that kind of stuff, right? Church has a lot of power over the people? 
He takes the kid with him on the trips? I also assume the kid takes over some of the demon's personality as he was raised by him, right? 

I think I'd like the kid to be from a rich family. Big house, richly decorated and a fence surrounding it. Just to make things easier to remember.