Drowning ghost story written in the ghosts perspective

I read it before September of 2021 so it’s gotta be written before then. I don’t remember the names of the characters or anything, but here’s what I do remember.

I believe the story starts on a beach at night, a group of people are drinking around a fire and talking. One of them brings up the legend of the ghost that comes back to life once a year to drag someone into the water and kill them. I believe the book takes place on an island, all of the people in the town know about the legend.

The book has a plot twist where the reader realizes at the end that the POV they’ve been reading is the ghost that’s come back to life, showing that the legend is real. I don’t remember if the ghost does kill someone that year, it’s been a long time since I’ve read the book.

The book is not from a detectives point of view or about the writer trying to solve her own murder. It doesn’t involve some sort of wealthy family or someone befriending the ghost.