Bizarre theory explains the next Will of D member to join Luffy to explore the One Piece world.
Oda reveals the next Straw Hat that no one saw coming!
The enigmatic aspect of the Will of D in One Piece has held many mysteries since the beginning of the series, and even as the series has entered its finale, no one knows what D stands for. All that is known is the identity of the characters who carry this will.
While one would expect Eiichiro Oda to have exposed almost every Will of D member, the end of the Egghead Island arc proves otherwise. The arch may be hiding another Will of D member, and there's a chance this soon-to-be-revealed member will join the Straw Hat Pirates in their next adventure to Elbaf.
This character is none other than Jewelry Bonney, daughter of Bartholomew Kuma and a main character in the Egghead arc. Although it has not been confirmed whether or not Bonney has the will of D, a recent experiment done by Saint Jaygarcia Saturn proves that she indeed does.