Responses

Well I used to have a high fixation on marine bio before switching to genetics and neurosurgery to ultimately lead to my design career (the lore is crazy lol) but whales are like seals in that they have blubber which is basically dense fat tissue, and so their skin is fundamentally hydrophobic. His hair could be similar in human form given his biology technically speaking, but I'm pretty sure authorsan just likes drawing perfectly sexy men literally speaking
So it doesnt make sense that they dont know the orca turns into a man