I think that King may not truly be the last true Lunarian (I’m not counting the seraphim as they are artificially made). I believe that there are around two reasons for this. 1: we know that the celestial dragons take rare and endangered races as slaves, we have seen them do this with buccaneers and Kuma so why would Buccaneers be the only case of this? The celestial dragons could very well have Lunarian slaves that they keep secret so no one would try to steal and free them. 2: I know this is cliche but Lunarians may be hiding on the moon. From Enel’s cover story we know that winged races originate from the moon, so why wouldn’t lunarians, a winged race whose name has the word Lunar which relates to the moon be from the moon? We know they lived on the red line so it could be possible that when they descended from the moon they landed on the red line instead of the white-white sea or the ocean. I rest my case.