>>2193728There is never any kind of fragmentation for Rei proved in the original.
It's just a theory, and if true or false, doesn't change too much.
We don't actually know how they do it, because this is entirely an element of science fiction that cannot be replicated in real life, they can't show you how to do something we can't in real life.
In real life we can't even prove the existence of a soul or something like it. A billion ideas exist but nothing more.
In Evangelion however, we operate under the premise that yes, there is a soul, and yes, it can be manipulated. Into EVA's, and into bodies.
I don't think humans have any particular organ that stores a soul in Evangelion, at least none is shown or proven to exist, it's a tie-in with their consciousness perhaps.
