Curves and Waves by Kalli Dean

This is a short, brothers best friend romance.
Zoe’s relaxing cruise takes an unexpected turn when her brother invites his best friend, Caleb – the man she’s secretly loved for years. As they navigate the choppy waters of attraction and friendship, Zoe and Caleb find themselves drawn into a steamy vacation fling that threatens to capsize their relationship with Jake.
But what starts as a shipboard romance quickly deepens into something more.
Will their cruise fling survive in the real world, or will they find themselves lost at sea?