sometimes illiterate just isn't enough to descibe the record-low IQ of one of your fellow friends. Illiteratable was developed for this reason and adds a little extra kick to the overly-used blan illiterate.
The stupid bullshit women read in their spare time; everything from trashy, soft-core (and slightly rapey) "romantic" novels, to Cosmo and self-help books. May include vampires, serene landscapes with big, sweaty farmhands, and coupons for Ben & Jerry's.
Girl: Is 50 Shades of Grey fiction or non-fiction?
Guy: Neither, it's illiterature.