Is Gekko Moriah human?
This is all we know about him being a human :-


  Moriah is a gargantuan person with very distinct devil-like features.
  Standing at 22' 7'' in height, he is the tallest among the
  Shichibukai. His animal theme is that of a gecko based off his name,
  general appearance and the collar of his shirt bearing a resemblance
  to a lizard's frilled neck. His overall design resembles a giant leek


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