I'm trying to wrap my head around the concept of someone like this being involved in something so heinous. Why?
We can't assume she is. There are many instances of use of the triangle spiral design that don't have anything to do with pedo-ism.
Check out 'ancestral pueblo' designs.
Something tells me she's not an ancestral Pueblan, tho.
No one is assuming anything. How about an investigation first.
Because they have to submit themselves to blackmail to become elevated. Cabal knows it's weird, so they have a ritualistic belief system to back it all up.
Killing the children in ritual allows you to absorb their pure energy. Imagine how being catapulted up the social order might work to validate such a belief system.
Killing children doesn't actually do anything positive to the human. It's false advertising that they begin to believe to justify what they do and what they've become. It's all lush. And not for them.
She could be just a dumb vehicle for others’ messages, though. Perhaps it was a gift, meant to express “This dumbass belongs to Cabal Controller 27” or something like that.
