Song of Lorelei by Desirée M. Niccoli

Her song is a lure he cannot resist.

Even after brokering a deal with the vicious merfolk who stalk his offshore fishing lanes, Captain Killian Quinn has had one too many onboard his boat for comfort. His livelihood, and life, as well as that of his crew’s, depends on his ability to maintain peace. One wrong move and the Dawn Chaser could become a floating charcuterie board, and he’d never see again the one mermaid he wouldn’t mind take a little nibble out of him.
A sinister craving for human flesh leaves Lorelei Roth with no other choice. She must aid the study of one of her own to find a more permanent solution to protect the ones she loves. As enthralled by all her sharp edges and seductive siren song as her fiancé may be, the threat of becoming the wrong kind of snack is never far enough away.
While they’re close to a breakthrough treatment, doubt gnaws at Lorelei as she watches a fellow mermaid languish in a tank, enduring endless rounds of tests and denied the healing touch of the sea. Is one mermaid’s declining health and happiness too steep a price for freedom? And if so, what sacrifices is Lorelei willing to make to set it right?