It really comes down to how you define "sexy". Erotic or pornographic shouldn't be in a public library, and if you want that, there's thousands to choose from in stores (more popular in the USA), or just nip down to the local newsagent and pick up a copy of Razzle there (EU).
I suppose horror/suspense reads aren't as graphic as films. Now, that's a stereotype or wild guess at best. But do they really promote violence? People aren't advertising these books on TV or showing live-action depictions of what's going ot happen in the book. We're safe from violence like this.
As prettynutjob30 says, we are censoring a lot but (metaphorically speaking) teaching children how to arm up. And yet somehow people younger than the age ratings have access to so-called violent video games and film....?