This is the relevant reference from the Books where Brand Guess is mentioned.
I make no pronouncements on these matters, but report them as I find them.
Arrive at your own conclusions.
I wish you well,
Better these fellows had been running about the windy corners of the markets, looking for the veils to blow about the faces of free women or pursuing slave girls, pulling up their brief skirts, playing "brand guess," or busying themselves playing stones or hoops behind the shops.
Renegades of Gor Book 23 Page 266