No yeah I know that about the different factions. I moreso mean the actual mechanics of why she came to have, at it seems, a conscience whereas other predators did not. It's another mystery from the story.
Well, Soyeon and Jeongtae have also acquired consciences. I agree it's not been thoroughly explained, but from how Soyeon said it happened to her, I think once a predator gets enough souls, they're able to completely transfer to this world and forge a body for themselves. When that happens, I think the memories and personality come from the last soul they consumed. It's interesting, though, that in the fake Minji's case, the soul overwrite was so complete she actually thought she was Minji, but I think her case is special because when she was a monster, she mentioned Minji was "something incredible" and eating just a fraction of her soul was enough for her to transition.
Which makes it all the more important that they recover Yun-ho's soul from the predator's body, because I think if it keeps consuming souls, it will become impossible to separate them again.