Clearly the one we're searching for is shadow .The eye declared itself as the origin of everything, that is to say, the one that exists prior to and superior to the apostles and all others. Therefore, the monster acknowledged its authority.
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Here he refers to the fact that on Earth there is a girl whom he needs in order to be complete. And who do we know possesses an even greater potential than ours? That's right, Emily... she is the missing piece for the eye to be whole. I can even speculate that she harbors the mysterious creature of death, "too strong too soon," within her. View attachment 2631836 View attachment 2631843
Personally I don't think it's Emily, but it is possible it could be her, more points towards it being Ella, or else we would've never likely showed up at her fight, since we clearly don't give a shit about anything else but becoming complete. It's also possible that Ella just knows where said person is, and it could very well be our human Mom for all we know, who knows if she's actually dead or just been in hiding or sleeping/coma or whatever. Probably just Ella though, since she feels a bit like both the main/true love interest and an antagonist at the same time.