John Norman 
Plunder of Gor 

Explore the counterearth of Gor—where men enslave women and science fiction and fantasy combine—in the latest installment of the long-running Gorean Saga. A mysterious package lies unclaimed somewhere in the great port of Brundisium, and it is rumored that its contents could determine the fate of a world. Whether or not that is true, one thing is certain: Men and beasts will kill to claim it. Meanwhile, a young woman, now merchandise, has been brought to the slave markets of Gor after displeasing a stranger in her secretarial job back on Earth. Unbeknownst to her, she holds the key to finding the elusive package—and changing the course of history forever. Inspired by works like Edgar Rice Burroughs’s John Carter of Mars novels and Robert E. Howard’s Almuric, this adventure series—alternatively referred to by several names including  the Chronicles of Counter-Earth or the Saga of Tarl Cabot—has earned a devoted following for its richly detailed world building, erotic themes, and mash-up of science fiction, fantasy, history, and philosophy. Plunder of Gor is the 34th book in the Gorean Saga, but you may enjoy reading the series in any order.