My novel "Taker" is set in the Regency Period of England, and as such required a great deal of historical detail, and while there are a lot of Romance novels set in that era, very little SM erotica can say the same.
For instance, Covent Garden was filled with entertainment spots and brothels of every description, and looked nothing like it does today.
Here is a period depiction of a brothel. Note the birch rods on the wall. BDSM is not new.
The poorer areas, such as the infamous Whitechapel could be grim.
While the haunts of the upper middle classes were much nicer. Shopping was popular at that time too.
On the other hand, life was not as prim and filled with prudery as we imagine. Without modern conveniences, people often had to make do.
Entertainment could be dignified or as rowdy as you wanted.
And politics was not always gentlemanly.
Prostitution was open and easily accessible. There was even a published guide to the girls, with reviews!
https://suite.io/rupert-taylor/2gvg238There were BDSM brothels too!
https://en.wikipedia.org/wiki/Theresa...You have to know how to get undressed!
http://historicalhussies.blogspot.com...And you have to know about the Thief Takers themselves.
https://janeaustensworld.wordpress.co...Much of the research was done on an interesting site "Suite 101.com" which no longer exists except on the "Wayback Machine". Its replacement is nothing like the original and has lost its academic focus. I still have copies of the site pages in my research directory, covering subjects such as "The Sex Trade in Georgian England" and "The Reticule - A Regency Handbag".
I hope this has been an interesting dip into the workings that go on behind a novel, even an "erotic" one such as "Taker".