Quote Originally Posted by Kraco View Post
That is a good threory, although on the other hand both Hikari and Kaname are abnormal cases also because they were left wherever to sleep. There might be some epicenter to the phenomenom, and we know there's the border than cannot be passed around the sea town. Were Hikari and Kaname even properly inside of it?
Not sure, but they sure weren't recovered during any form of rescue event. We never saw any scuba-diving in this show, but they did mention that the humans couldn't reach Shioshishio.

Miuna starting to breath underwater came out of nowhere. It also could be the first time people could move from the land to sea, so it should be quite a significant event.
It could be, but then I remembered that her mother was a seafolk. Whether humans are now gaining underwater abilities from this event, or whether it's just by chance that Miuna can breath there is still a debate I'm having.