I do remember that Mignola story, it has loose elements from the Little Mermaid, the Sea Hag/Witch etc. Good story.
In regards to the manta bit from Subby 33, I don't at all mind something like that, at least the idea of it. Something that's an ancient ritual, something ceremonial or traditional that is being adhered to. Though, going all the way to the mid pacific is quite a stretch. Unless he wanted to make that trip over like 100 days.