I have have read a comment saying that Big Mom’s remark of ‘Cat Burglar’ is Japanese slang for Husband stealing or seducing a married man.
This idea when looked at into the context that when a couple become married, they become soulmates. This could be a subtle hint from Oda foreshadowing Zeus gaining free will and thus choosing Nami over Big Mom or in a different sense being seduced by Nami.
Think about it. Big Mom has the soul soul devil fruit, which specifically takes and gives souls to objects. So Big Mom having her own soul betray her to join Nami would be a fitting end to her character arc.
You see Big Mom’s amnesia and her hunger tantrums could be a direct issue of her giving away her souls to tangible objects. Looking at how Big Mom steals people’s souls and life span forcefully away from them and in turn loses her own soul stolen from her making Big Mom in other terms, a shell of her younger self, so what happens in Wano is that Kaido is defeated and Big Mom becomes non-threatening. Then Katakuri could step in and become the leader of the Big Mom Pirates and thus the old generation of pirates are taken out of the picture and the new generation battle out for the One Piece.
This could be a fire way to reach Big Mom’s character conclusion, the irony would be crazy.
I mean you look at the themes of One Piece being freedom and Luffy’s personal dream of being the most free in the world and the least free thing in One Piece is probably the soul, the way its chained down to the person, this would be the most appropriate way for Zeus to become a Straw Hat.
*Theory by UziBeenHoopin
