From the Immortal Fire Anthology Different worlds, different expectations, but when a Captain saves a Prince, it may be the Prince's love that saves the Captain. There are three main characters, it's a love triangle, where they could all end up in a trio.
They are Captain Faith Denen, Yee the Leche, Nathaniel Lath Rizen Vin Rayn, Duke of the Emerald Coast, Lord of Trimern, Crown Prince of Elestrian. The world is a far future world, where landfall was made on a distant planet and technology not retained... so that the people are living much closer to the level of Europe in the 1700's. The culture is split between High Town and Low Town. Nathaniel is the heir to the throne. Faith is the captain of a merchant ship with a disreputable family history. In Time, Faith and Nathaniel are trying to escape the palace and Faith comes into possession of some very ancient magic that will make him the ultimate protector of his prince. It'll make him immortal, but every immortal life starts somewhere.