From The Depths || Writer's Lagoon Prompts

In which I steer clear of witches and move to mermaids, sirens, and all things ocean -- something interesting considering I'm very hydrophobic and that's saying nothing about thalassophobic!
These prompts -- mostly -- come from 'Writer's Lagoon' by talesofthedeep (link in my conversations), and I'm gonna try to answer every prompt, not necessarily in order -- I might write 20 before 14, for example. I'll put the number of the prompt according to the book in the title of the chapter, so you know where to be looking.

Symbols in the title (||, \\, //, etc.) show which story 'set' it's linked with. If it's just a : then there's nothing else linked to the story within the book. So far:

St Mhairi = ||