Saltwater Heart — Kendall Kulper

The summer James lost his heart to Alice, Alice lost her heart to the sea. The confident and charming daughter of the town's most accomplished whaling captain, Alice changes James's life the moment she teaches him how to sail. But when her father needs to fill a spot on his ship, it's James who is offered the position, and the day he returns from his expedition, he discovers Alice has disappeared.
In this companion novella to Salt & Storm and Drift & Dagger, James must search the world for his heart's desire, a journey that takes him from the strange and mysterious world of the infamous Roe witch to the deepest and most dangerous reaches of the ocean itself.