The only people who know the ending of One Piece are Oda (as said in a previous chapter, the creator), his editor, and a kid who had cancer. The child's last wish was to know the end of his favorite anime before he died, so Oda met him and told him everything.

A/N: Woahhh, that's so sad-- but at the same time, Oda is so compassionate.. May the child rest in peace. T_T