Siren in Love by Alexa Piper

Mike is a siren with a law degree, and he’s straddled his supernatural heritage and living among humans for years without a hitch. Yet, dating a human is a first for Mike.
Corvin is bookish, cute, irresistible. It doesn’t take long before Mike knows he wants to share all his melodies with him. And it should be that easy, except the good things in life rarely are.

Siren in Love contains some gore, minimal decapitation, a hangry vampire boss, and books. So many books.
(Note: this book was previously published as Siren’s Love Song. The story has been expanded on for it’s re-release.)