Pierre Benoit 
Atlantida, Or, The Queen of Atlantis [EPUB ebook] 

It is 1896 in the French Algerian Sahara. Two officers, Andre de Saint-Avit and Jean Morhange investigate the disappearance of their fellow officers. While doing so, they are drugged and kidnapped by a Tarqui warrior, the procurer for the monstrous Queen Antinea. Antinea, descendant of the rulers of Atlantis, has a cave wall with 120 niches carved into it, one for each of her lovers. Only 53 have been filled; when all 120 have been filled, Antinea will sit atop a throne in the centre of the cave and rest forever. Saint-Avit is unable to resist Antinea’s charms. By her will, he murders the asexual Morhange. Ultimately, he is able to escape and get out of the desert alive. (Wikipedia)