Man Overbored

Large print for those whose eyes are as bad as mine
Cliff Hardy was bored. Here he was, sitting in his sailboat in the Caribbean on a full moon romantic night, alone.
He sighed, and read the titles of the books on the little shelf. All about voodoo and zombies and that kind of stuff.
Well, he was near enough to Jamaica and Haiti, where that stuff was practiced.
He was bored. He was there. What if...?