Basic
DIALS ARE ONLY FOUND ON SKYPIEA. Your character cannot just "have a dial" for no reason whatsoever! There has to be something in the history for why they have one. If they have not been to Skypiea, then they shouldn't have one. And if they haven't been, then there should be a good reason for why they do have one. And not just "He/she stole it from some passing pirates." well for the pirates to have it, they would have had to go to Skypiea, which can only (so far) be accessed in the Grand Line, so they would have had to go all the way through the Grand Line (or leave through the Calm Belt). Plus, most pirates believe Skypiea is just a myth, so that makes it even more unlikely for one to have it!
In short. Your OC MUST HAVE A GOOD REASON FOR HAVING A DIAL. Either they've been to Skypiea, or some other great reason for them to have one. They can't just have found it or stolen it, despite what you may believe, dials are not everywhere! Not everyone can have one. Live with it
