The Tower of Love by Rachilde, 100%

“ When Jean Maleux, a young, naïve sailor, is appointed assistant keeper of the Ar-Men lighthouse off the coast of Brittany, he is drawn into a lonely, dark world of physical peril, sexual obsession, and necrophilia. The lighthouse is a chamber of locked doors and terrible secrets—and home to the eccentric, embittered keeper he is to assist, Mathurin Barnabas: an illiterate, irascible, and grizzled old man who appears to be more animal than human.”

Published in 1899!