The Witch Sea - Sarah Diemer
Lovely, simple, and enchanting.

The Witch Sea is a short story about a sea witch named Meriel who inherits a great responsibility from her grandmother. She must tend to the spell that binds a sea god and prevents him from destroying humankind. But when a beautiful selkie girl slips through her spell, Meriel finds herself torn between obeying her grandmother or setting the sea god (and the unfortunate sea people who were caught onshore with him) free.

This is the first work by Sarah Diemer I've read, and I'm definitely planning to look at her other stories. The prose is gorgeous - lyrical but without any filler - and the story really evokes a sense of place.