As promised, here's CJ's (sort of) origin story.
I tried to make it feel like a sort of twisted fairy tale.
This also explains CJ's Scrappy-like ability given by the curse-induced mutation; the ability to hit demons, ghosts, and other otherwise-intangible monsters is an echo of Erin's killing a fairy, a being typically thought of as being invisible, undetectable, and intangible by most people (or those who don't "believe" in them enough to see them) being mortally wounded by a human weapon (an arrow.)
And before you whine about "DATS NOT HOW IT HAPPENED!1" this is an ALTERNATE UNIVERSE.
CJ is NOT the canon Jeff, and this is NOT the history of the canon JtK's bloodline. It's CJ's. Okay? Okay.
Jeff the Killer (c) creepypasta
Cannibal Jeff (c)
More CJ: laserpotato.deviantart.com/gal…
CJ's bio: laserpotato.deviantart.com/art…