Exactly how steamy is this story?
PG-13
As far as steaminess goes, Dune is very much like watching a classic movie. You know, the kind where married couples sleep in separate beds and teenagers propose with promise rings before they hold hands at the movies. People are having sex—they have children, right?—but all the sex and sexuality is kept suggestive and in the background. In the foreground, the characters might as well be white-collared monks.
The same goes for Dune. Sure, people are having sex, but even the soldiers hardly discuss the act. The closest we get to a typical soldier's dirty joke is Gurney's occasional lewd limerick or bawdy tune. And, to be fair, Gurney keeps it pretty classy.
Then why the PG-13 rating? That's because some of the stuff happening in the background can be super adult. There is mention of prostitution, sexual slavery, pedophilia, eugenics programs, and women purchased as concubines. Again, none of these things actually occur in scene, but there is reference to them, and their presence lingers throughout the novel.
So, we at Shmoop suggest a little extra age before diving in. You should be a bit older than the Star Wars crowd, but you don't have to be ready for A Game of Thrones.