As we're all aware,there's quite a debate going on all over social media among fans regarding Sanji's sudden disappearance. Now, the reason why this whole altercation is heated and is slightly more contraversial than other discussions is the character's(Sanji's) background story being shrouded in mystery,meaning that his past is not very well understood. Yes,we know he was part of the Baratie crew but what happened earlier in his childhood before that, we simply do not know...yet.
That's why I decided to share my own thoughts on the matter.
Here's my Hype-othesis. (pun intended)
When he reunited with his crew after a 3 year "break", Sanji just wasn't the same,grew his hair and all that.Being in the same ship with a reindeer, a cyborg and a skeleton just wasn't feeling right for him. So when Sanji & Co took a different route from the rest of the crew, Sanji saw an opening and went for it.What I'm saying is that he went back to Okama Kingdom...SOMEHOW.
The reason why he did it. I don't exactly know,nor does modern science/psychology.Apparently, there's this psychological phenomenon called Stockholm syndrome (seriously look it up)where hostages express sympathy toward their captors.This explains Sanji's leave perfectly.
Here's a paragraph taken from wikipedia explaining this phenomenon:
Sounds familiar doesn't it?
Basically,he couldn't bear the absence of his fellow okama friends any longer so he made up his mind to go back.
As we all know,Oda is a master of foreshadowing.Now what if I tell you that he succeeded in his expertise once again and surprised us yet another time with his artistic foreshadowing.
This panel was taken from chapter 806.
And is merely a foreshadowing of this:
This means that Sanji told Nami that he wants to go back and that he doesn't find her nor any other woman including Robin attractive anymore.That's why she's crying, obviously.
Do you agree with this theory ? Let me know in the comment section below. Also,don't forget to add your own prediction on what's going to happen to Sanji next. See you around guys.