LOL. Sorry, but that must include most of what is posted on this site! You really think all the stories posted here have a plot? Some are more accurately described as scenes or vignettes. Others are simply endless ramblings on the author's particular kink, that have been quite literally been ongoing on for years (yes we all know which ones!). I hasten to add that there's nothing at all wrong with any of the above providing it is written with a degree of skill and attention. However...But presumably, all stories should have a plot. A story with no plot is a story of bad quality, not a special type of story.
I agree with other readers that a plot development, and an original scenario are major attractions for me. I like to enjoy the writing and the author's writing style and ideas as much as being aroused by the story.
Anyway, that's my 0.02 Euros worth.