Person who writes Porn or Erotica. Interestingly, there are lots of people who like to read pornography, erotic stories, and so on...even it they won't admit it.
Some PornWriters and their favorite genres include:
FessNelson - Erotica, including fetishes such as stockings and food, some S&M.
EvilSouthie - Haven't written for ages, but was erotica, voyeur/exhib, some femdom
MacKenzieStuart - Softcore Wiki porn found at WhyGodWhyWouldYouWriteThat