While there are dozens of websites and mobile apps for connecting nearly every type of person to some sort of compatible other, there are few options for those who might be otherwise attached to explore and fulfill their desires. This demographic is otherwise forced to disguise themselves and their intentions on sites not entirely envisoned for their particular requirements in the hopes that may, mostly by random chance, might find someone in the same situation.
While there is one, dominant, player in this space and a few communities that indirectly can service this demographic - there is significant opportunity to develop a platform that specifically caters to the needs of those seeking affairs and casual relationships without risking their privacy and needs for discretion. A platform that enables interested parties to find each other by availability, proximity, desires, and other criteria while still allowing them to maintain complete anonymity and discretion. A web and mobile platform allowing discreet registration, search, communications, pictures, feedback, and other services. The platform could be monetized through premier services (prefferd search results, unlimited messaging, unlimited browsing, etc...), advertisements, and partnerships with related industries.
A potential partner need not be a participant in these activities - there are ample means to explore exactly how this opportunity can be exploited without actively participating. Instead, the ideal partner needs to recongize the growing opportunity to service those looking for these types of connections. A clear understanding that simply servicing a growing need is not necessarily an editorial comment on society.