Zou might die after Luffy’s visit.
According to an Indian myth, the world is on the backs of four elephants.
Here Zou is just one elephant in the sea. Zou might have something to do with the 4 seas.
4 elephants into 1 elephant = 4 seas into 1 sea… the All Blue
According to the myth, the ‘world’ is on the back of 4 elephants. The world = the world’s secret i.e. the secret of the world government… the void century.
On the back of Zou resides a race of people, the Minkmen who hate humans.
There was a prophesy that Luffy would bring destruction to Fishman Island and then the Merfolk & Fishfolk would move to land. Though it might seem like a bad thing, it’s a good thing. To unite humans with the Merfolk & Fishfolk. That was the purpose of the Noah, to transport them.
Much like Fishman Island, the death of Zou is actually a good thing. The 1,000 years old ancient elephant has a cursed expression. It looks tired and cursed. It’s possible it’s cursed to roam the seas for eternity. It might have been wishing to die for centuries but cannot. Luffy might directly or indirectly free it from the curse. Also, it will force the Minkfolk to live among the humans again, uniting the people of the world.
I wonder what role the Will of D. have in this
*Theory by Capt. Awesome D. Shin