Plot Hole or Inconsistency? SPOILER!!
Was Paimon ever in Charlie to begin with? Yes I know everyone thinks that he was or some part of him was in her, but her being female wasn't ideal. But if that's the case then why did Charlie "see the light"? That light that traveled about in the film to show I guess Paimon's spirit trying to find a host.
In the end we see the "light" once again finally shine on & stop on Peter's dead body & then "enter" it. But once more if Pai was in Charlie the whole time then why would she even see it outside of her to begin with? Meaning I don't believe he was capable of leaving her if he was already in her (unless she was dead) to go & try. That doesn't make sense but maybe someone here has a explanation.