Books like Slave Girl of Gor
John Norman
Slave Girl of Gor is 564 pages, about 10 hours 20 minutes at 250 words a minute.
12 books to read next
How long each takes
A Game of Thrones 14.7 h 
All You Need Is Kill 4.7 h 
Ancillary Sword 7.6 h 
A Princess of Mars 3.2 h 
Sleeping Giants 6.2 h 
Record of a Spaceborn Few 6.6 h 
Aurora 8.6 h 
Zero Sum Game 6.5 h 
The Gods of Mars 3.7 h 
Area X 16.6 h 
Deathlands 6.4 h 
Star Wars - Catalyst - A Rogue One Novel 7.9 h Bar height shows length. Estimated at 250 words a minute.