Take Edgar Rice Burrough's Tarzan, H. Rider Haggard's Lost Civilizations and John Norman's Gor and as your heroine princess raised to believe she's divine and men are extinct and you have the world of the Atlan Saga. The City continues the perils of Princess Cija, who falls into the clutches of Sedili, the first wife of her lover Zerd, a man-serpent general. Cija does grow on you, which given these are supposed to be her diaries is important. So, this is the description of the book on Goodreads:

Endless Peril...Anguished Fate! Rescued by a bold sailor, held in the confines of a lascivious brothel, Cija faces yet another life-and-death ordeal. She escapes but her respite is short-lived. Treachery and betrayal sweep her into the temple of her hated father, beyond a terrifying, sensual interlude in the Arena of Apes. With the seed of her ape-man lover growing within her she is carried to her ultimate destiny inside the monstrous walls of Atlan...

Yes, really. Sometimes I'm embarrassed to admit I've read these, let alone these are favorites that have been on my bookshelves since my teens, but there you are. Addictive like crack. Or just crack pot. ( )

Cija escapes her dragon husband Zerd only to find herself expected to work in a brothel, then becomes the lover of a forest man.....

The City by Jane Gaskell (1966)

Have 1970 edition, Paperback Library ( )