Interesting discussion of the "soul" thing.
My thoughts? The "soul" gets shaped by experiences, it grows. In the case of f.i. Tina, I really believe (in the Wapsi-canon!) Tina got a "soul" through the demons deciding that doing "good" was more satisfying than being evil, and acting upon it. At thát specific moment, her soul became a reality. The cute thing about Tina, is that she's convinced she has no soul, and to me that's exáctly why I believe she has one.
Only by having a "soul", a character can understand and feel the importance of a soul.... Think that one over for a bit. "I think, thus I am"
Think f.i. of religious people. To thèm it's the most important thing in their lives to believe what they believe. To have a discussion with them, I have to imagine their Deity as a real, living entity -otherwise you'll be discussing about nothing, massively complicating things. And at thát moment, the Deity ís real, for me too, despite being an atheïst, if only for duration of the discussion.
A problem that has always stumped philosophers.
The Nu Gui was (to me, at least!) not a "soul", but just an entity hellbent on evil and revenge. It's often said that being full of revenge, will destroy a soul. In the Wapsiverse, I can imagine it to be reality.
But, then again, I am an artist, academy of the arts educated. To me a piece of art can have a "soul", be it a soul that's put into it by the artist. So, the "soul"-thing is more fluid to me than simply the nucleus of a living, breathing entity. (Or nót breathing, for the GG.. ) the clay-jars have a sense of right-wrong, they ponder existence, and thusly -again, to me- have a "soul", but they do not realize it, because they are convinced they cannot have a soul. The 'hole' is only there in their imagination, through their conviction they cannot have a soul. And in believing that, they project it as "reality" to the rest of the world.
Maybe it's a way to work through their traumatic past. Their violent Chimera-state, was the result of aimed removal of their souls by the priests, their rituals wholly aimed towards using just the anger and hate of the girls. The anger and hate fostered by their horrible deaths (Hey, magic, you know? ) In the Wapsi-verse, anger, hate, spite, all of those negative things, can apparently be separated, and used by a sufficient adept clique of priests/magicians, to shape an entity out of it.
In case of the chimera, they failed, because Jin chose her own death, and thusly leaving part of her "soul" intact. I wouldn't be surprised of having a "soul" is contagious too, in the Wapsi-verse. What I mean is this: If making a Chimera, be careful to destroy ALL vestiges of a "soul", otherwise, the chimera will be "tainted" and the tiny bits of soul left, will, like a bacterium, grow like mad, wrecking the chimera by imbuing it with a "soul" again.
In this case, the "good" part of Jin witnessed the carnage, "infecting" Bud and Brandi with her horror&shame, and planting the seeds in them for restoring their "souls" too. With all the results for the GG, in their quest to atone. *shrugs* seems logic, at least to mé, it does.
But hey, it's just the musings of a flunked philosophy major... About as valuable as €0,01, or a used paper plate at a BBQ.
So don't attempt to engage in a really deep metaphysical discussion with me. I'll only look back, mouth half open, unable to say more than "eeeeeehhhh" (imagine drooling idiot here

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