Just One Look by Deb Julienne

On a secret mission for her entrepreneur father, Diana Tolliver (aka Diana Clay) finds herself unexpectedly alone on a singles cruise. She befriends another solo female passenger, and they play a game to make their would-be-boring cruise a bit more fun. Each woman must pick out a single male for the other to date for the duration of the cruise.
JJ Westbrook is working his final gig as band manager for his best friend, country singer Hunter Cross, leaving to pursue a new job. While on the deck of the cruise ship, JJ spots a blonde goddess and is captivated.
When mutual friends reconnect, Diana and JJ are set up and quickly become enamored with each other, but only have a few chances to sneak away together during their time on the ship. Will they be able go their separate ways after the cruise, or will romance—and careers—bring them together again?