^^That is one tradition, but equally, there are others where they don't seem to have any particular connection, where Ibaraki-Douji was raised by Shuten-Douji, etc...
Okina is not taking the divorce well, I see.
It's another one of those "Well, if you know the mythology..." ships. Centipedes, especially where mines are concerned, are Bishamonten's messengers.
Hoping to see more of this, honestly!