This book was ok. I enjoyed it and made my way through it quickly.  My main complaint was the writing style was overly formal which made the characters seem stiff and cold.  
The book with the FMC and the love interest #1 as at least a  4⭐ read.  The merman was cold and formal but it worked as there is something alien about a creature from the cold part of the sea.  Unfortunately the other non human characters have the same stilted narrative style.  It's hard to see how the FMC falls in love with all the characters.   

The plot is a bit sticky as well.  It's predictable and the attacks become repetitive without bringing something new to the story line.  

I feel there is are good concepts here but the author does not seem comfortable with where she is going with her characters and their arcs.  
I picked this book in a stuff your Kindle event.  The rest of the series is not offered on KU.  If I am not able to find this series in a library app I don't think I will continue reading it at this time.