The terms "porn", "masturbation" and "orgasm" really don't have to be spelled out in everyone's signature and in everyone's face, in various types of topics. You don't use those words in every-day conversation, because they are bomb-shells. Imagine suddenly telling a co-worker about your orgasms, or about masturbation. Sure, that's what we are talking about here, and we are all familiar with it, but I think care and sensitivity with wording is still (especially here) appropriate. I'd suggest sticking with the communally and easily understood abbreviations P/M/O.