FemBATS is an abbreviation of Females Burning at the Stake (in fantasy terms only, I assure you). It's usually the end result of all those wonderfully wicked medieval torture stories that I have penchant for!
Aaaahh, thanks for clearing this up - I was close to dying of curiosity, lol. And no, you haven't alienated yourself yet...quite the contrary - medieval torture got me hooked on many a book or movie.