You know what's ironic about the
theory?
Someone brought up the theory back during the Wild Mass Guesses for ULiL, citing the
Forbidden Scrollery chapter in which
, and used that to explain how
might have an appearance in ULiL, possessed by the then-unidentified "Hanako". That turn out to be not the case:
isn't even mentioned in ULiL, and "Hanako" is revealed to be the fully-human Sumireko. The jossed theory is, funny enough, forgotten within the same week it was brought up, and that's before ULiL full version is released.
But then came FS chapter 50, and suddenly, everyone is finding
as a
highly likely possibility...