SPOILERS: Whats the purpose of the Snake fruits?

[The West Nile Fever]

I managed to nab both of them on my first playthrough, and yet I finished the game and found no use for them. Anyone know?

[Killance]

To feed them to the fake divine child. Its to get the "Return" ending. Just one of four endings.

[The West Nile Fever]

Ohhh I completely forgot about the girl!