The “Will of D.” is a mystery surrounding some people who have the initial “D.” in their names. It is not clear what the significance of the shared initial is, but it appears that all share a deep desire for freedom and have strong faith in their own (and others’) dreams and/or destiny.
When a “D.” appears, the general consensus is that they are going to stir things up on a global scale, for better or worse. Examples of world-shaking events instigated by “D.”s include wars, changes in government, and the dawn of a new era. The Will of D. could be seen as an example of the broader concept of Inherited Will.
The biggest mystery of “D.” is that most of those who carry the “D.” are themselves unaware of its true meaning. However, it seems that the Marines have some awareness of the initial’s significance, as Sengoku showed interest in Ace because of it.
Trafalgar Law’s parents also seemed to have some knowledge about what “D.” meant, considering that although they passed down the initial to their child, they hid it and insisted on using only their surname and given names. Gol D. Roger is the first and, as of yet, only known “D.”-bearer in the storyline to have discovered its meaning.
Those who bear the “D.” in their name seem to be able to withstand an incredible degree of punishment in battle and only surrender to death when they know it is truly unavoidable. In the same vein is an unusual behavior that seems to be common to “D.” – they are often seen laughing or smiling right before they die (or think they are about to die), as though they have accepted their fate and hold no fear of death. Observers have expressed shock and confusion at this phenomenon, unable to believe that someone could so thoroughly come to terms with the end of their life.
So far this strange trait has been shown 6 times:
- Witnesses claim Gol D. Roger died smiling during his execution.
- Smoker saw Luffy smile in the same way when he was about to be killed by Buggy, though he survived in the end.
- Nico Robin witnessed Saul laughing and smiling as he was frozen to death, though he survived in the end.
- Portgas D. Rouge is seen both crying and smiling when she named Ace, dying shortly after.
- Portgas D. Ace thanked everyone for loving him and died with a smile on his face.
- Trafalgar D. Water Law smirked at, mocked, and flipped off Donquixote Doflamingo when the latter was pointing a gun at his heart and preparing to shoot him, though he survived in the end
Blackbeard is unusual among those with the “D.” in that he has shown fear of death. When Whitebeard attacked him at Marineford, he started to panic and begged for mercy. Blackbeard, though he did not show fear when fighting Ace, could not accept death when it became a strong possibility.
Right when Vegapunk mentioned that devil fruits are related to desires I immediately thought that the “Will of D.” HAS to be the “Will of Desire”. I think that the people with the D. in their name are the ones able to manifest their desires into devil fruits.
I think that is why they scare the World Government. If someone with a D. in their name becomes strong enough they can create their own devil fruit. Either that or they were the original group that created the devil fruits and maybe have more power with the fruits. At one point devil fruits were most likely called desire fruits and sometime during the Void Century the World Government changed their name to devil fruits to try and hide the meaning of the D. name and to try and get people to not eat them.