Stealing the Wind: Mermen of Ea, Book 1 (Unabridged)

Taren Laxley has never known anything but life as a slave. When a lusty pirate kidnaps him and holds him prisoner on his ship, Taren embraces the chance to realize his dream of a seagoing life. Not only does the pirate captain offer him freedom in exchange for three years of labor and sexual servitude, but the pleasures Taren finds when he joins the captain and first mate in bed far surpass his greatest fantasies. Then, during a storm, Taren dives overboard to save another sailor and is lost at sea. He's rescued by Ian Dunaidh, the enigmatic and seemingly ageless captain of a rival ship, and Taren feels an overwhelming attraction to Ian that Ian appears to share. Soon Taren learns a secret that will change his life forever: Ian and his people are Ea, shape-shifting merfolk, and Taren is one of them too.