This just in: /tg/ is actually making a homebrew enjo kousai RPG. Only a basic structure has materialized so far, but the concept and mechanics interest me greatly.
I’m not too aware of enjo kousai, having only heard or seen it in anime on occasion (say, Mai-HiME). One thing to note is that it doesn’t always involve sex, and the game isn’t really FATAL. It’s more about juggling your purity and corruption levels, both of which help, deter and influence your gameplay, and hiding your activities in order to keep up your social standing. It sounds a lot like Magical Burst or Madoka Magica, where you will have to sacrifice a part of yourself to gain something, where consequences could be obscured until they can no longer be ignored or avoided.
As for me, I don’t think I’m playing… yet.