Responses
It will most likely be explained on the future chapters.
Personally, I like to believe it's just like the kdrama Legend of the Blue Sea where the mermaids cry pearls as tears. Jooha and his mom are *probably* mermaids, which explains them having paler skin, unnatural hair color, living near the sea, and releasing pearls.
So like where were the pearls coming from- kidney stones? Like dawg I'm so sorry but I wanna make some kinda sense of it WAHAHAHAHA