Kindle porn, or Kindle erotica if you like, has been rumored to be a not-so-inconsequential part of sales. But like many things Amazon, they provide little to no information or guidance on the topic. From what I can tell there is no Kindle sales ranking to help us back into the figure.

Here’s what I do know. As of this writing there are 3,844 titles listed under the Kindle Books > Fiction > Erotica category. That means Erotica comprises approximately 2% of the current Kindle catalog. By comparison, Literary Fiction has 4,487 titles. I’m guessing the distribution of titles is quite different outside of Kindle and that Erotica doesn’t have the same high rate of penetration when you look at titles in all formats.

Recently, a thread on FriendFeed developed around the following captured image.

The implication here is that there is a substantial overlap in viewing habits between Kindle and … ‘Sexual Wellness’ items. So, is there a greater incidence of purchasing behavior between the Kindle, erotic titles and … accessories? Perhaps. Or maybe Amazon just has their finger on the proverbial scale and Kindle is almost always presented as a similarly viewed item.

There is some logic to the type of items that are being presented above if you believe some conventional wisdom. The Kindle is black and white only with no picture capability. So it’s not going to attract the normal porn crowd but, most likely, will appeal to a predominantly female demographic who aren’t as visual as their male counterparts.

It would also be appealing since it is completely anonymous. Not only are you ordering ‘online’ but there is no delivery of the title to your home, nor would you have to hide a provocative cover should you be reading it out in public or in bed next to a spouse.

If this is an area where Kindle is gaining traction, I suspect that the sales by format would also favor digital distribution. As such, that could have a material impact on the one Kindle statistic Amazon does mention.

Kindle titles already account for more than 10% of unit sales for books that are available in both digital and print formats.

Fact or (Erotic) Fiction? What do you think?