I was just thinking after reading the last chapter that some information may be revealed concerning luffys ancsetory in this arc.In what gekko stated it would make sense. He said that the ultimate zombie he created comes from the leader of a nation of criminals that came from all over the world and this was 500 years ago. This devil guy could be a link into luffys D.,since all of the D have the D but not all realated and not all of the same species. The D could stand for allgience to the Devil form 500 years ago. Just specualtion but to me in sounds intresting and will give this arc a whole new apprecation
If you spoiler me, I will eat you with tater tots.