Would Koyomi be Medusa's gate?
It would blow out of the water the theory that the girl in the opening was Medusa's human self.
The gates usually die and the phantoms take the human form over. Koyomi is basically a shell and mana/magic is keeping that shell alive (living doll).
And... Who has said otherwise...? :eyebrow:
Who said what? That Koyomi is a shell? Have you seen the recent episode?
And... Who has said OTHERWISE...? :eyebrow: