How much sex is too much sex in young adult fiction?

Parents can do plenty of things to embarrass their teenager, but writing a novel about sex has to be up there with the worst. Which is why Daniel Handler, who is more well known by his pen name Lemony Snicket, is not surprised that his latest novel, All the Dirty Parts, has remained untouched on his 14-year-old son's bookshelf.

"The book could have come out when he was really too young to care and now it is out at prime embarrassment time for him which is regrettable," Handler says. "I know he has some friends who have read it but I certainly don't blame him being embarrassed that his father has written a book about sex."

There is as much sex in All the Dirty Parts as unlucky occurrences in Handler's famous 13-part children's book series, turned film and TV show, A Series of Unfortunate Events.

The novel consists of a series of fragments detailing the erotic fantasies, impulses and activities of high-school student Cole. They are narrated from his perspective and are at times ethically questionable, particularly when it comes to consent.

"Draw a number line, with zero is you never think about sex and 10 is it's all you think about, and while you are drawing the line, I am thinking about sex." Cole warns us early on.

The publication of the novel has not only caused discomfit for Handler's son. There was a lengthy delay between when Handler completed the book and its release, as his publishers debated whether it should be marketed as young-adult fiction. The decision? No.

"They were concerned that if we published it for young people it would be chopped off at the waist. That no one would have it in their libraries and no one would be interested in fitting it into the world of young-adult literature. It would just be too much of a hot potato," Handler says.

Handler says he witnessed how the guardians of young-adult literature - the critics, publishers and booksellers - remained "terrorised by sexual content". The harshest criticism, he says, emerged when the concept of the book was publicised and there was outrage it would be a "dirty book for children".

"If I had written a book about teenagers murdering one another no one would have thought twice about publishing that for young people. The idea that you could write a book about watching porn on your computer in your room and that would somehow be so dangerous that we better not let it in the library was startling to me even though I expected that it might happen."

There is perhaps some irony in excising sexuality, particularly male sexuality, from young-adult fiction. There is a well-documented gender gap when it comes to young people and reading. Handler says he, and other male authors, are frequently asked what ought to be done to encourage more young men to read.

"Having thought about what was interesting to me and to other people I knew when they were young men, certainly there is a lot of interest in sex and that is the one thing that is policed very sternly in the literature that we're giving to young people," Handler says.

Handler, who has published five other novels outside of the Snicket alter ego, has his own anecdotal evidence to support this claim. His mother recently cleaned out her attic and discovered a stack of books Handler read when he was a teenager. When he re-read them, he discovered they all had one thing in common.

"They were all full of sex and I hadn't really remembered them that way at all," he says.

But does All the Dirty Parts live up to its title? The novel touches on the themes that recur in young-adult fiction - friendship, confusion about sexual orientation, the joy of falling in love for the first time and the pain of heartbreak.

"I keep writing, and not just, I'm thinking, the dirty parts. There's more," Cole eventually concedes after he falls for the new student at his school, Grisaille.

This points to some of the questions Handler was interested in asking. What are the "dirty" parts and can you catalogue them from all the other parts?

"It's not a work of pornography and it's not the same as pornography," he says. "It's not something that is meant to titillate and to do nothing else but I like the idea of thinking about whether something is dirty or not. On the one hand everyone knows what you mean and on the other hand no one can agree."