The Invention of Morel (1964)
The Invention of Morel is a 1964 Spanish-language science fiction book written by Adolfo Bioy Casares.
A fugitive hides on a deserted island somewhere in Polynesia. Tourists arrive, and his fear of being discovered becomes a mixed emotion when he falls in love with one of them. He wants to tell her his feelings, but an anomalous phenomenon keeps them apart. - Wikipedia