Jezebel's Anna Holmes wrote in the New York Times that The Most Erotic Book she's read is Forever by Judy Blume. Which I love, because homegirl Judy got me through mini-boobs, bullying, and a weird fascination with Hitler, among other things.
But it's way easier to read (and celebrate!) other people's answers than to share your own. I was struggling to name even one erotic book I've read (never mind dubbing one 'the most erotic') when a memory struck me. I was riding the subway to work, innocently reading A Song of Ice and Fire (can't remember which), when Daenerys Targaryen's uh...curiosities emerged and surprised the shit out of me. In a good way! Suddenly I wanted to be home, in bed, reading under the covers and experiencing the warm feelz of burgeoning sexuality in private. That doesn't happen too often. 'Twas indeed a landmark moment in my personal reading history.
Now show me yours — what's the most erotic book you've read? Make some recommendations, I clearly need direction.