A New Brunswick mother says she was shocked when her 12-year-old son recently brought some graphic novels home from his school's library.

Christine Stillman says she is still fuming over the incident and is wondering how the graphic novels, which feature cartoon animals having sex acts and depict acts of violence, ended up in the library at Salisbury Middle School.

"She is on top of him, he's on top of the female chicken, she's telling him ‘don't stop, give me more.' Then the chicken is telling the pig, after she's been on top, ‘can I get on top?'" Stillman says in describing the novel's content. "It is not questions parents should have to our answer to our children."

An employee at a comic book store in Moncton says not all graphic novels are explicit and many are aimed at specific age groups.

"Anything probably 16 and above," says Matthieu Surette. "We usually check everything that we get in to see if there's any type of nudity or swearing or really graphic violence. Then we put it accordingly in our adult section, or our mature reader section."

CTV News spoke with a number of parents who said they too were shocked at the discovery.

"I'd be at the school and I'd be really, really upset," said one.

"You shouldn't have that in a school," said another. "It's inappropriate. You don't read it at home, so why would you read it there?"

Stillman says she would like to see more attention paid to what ends up on the shelves at her son's school library.

"I would also expect to pay more attention to the back of a book," she says. "When it says ‘for mature readers' and it says ‘graphic novel.'"

A spokesperson with the school district says they have asked the school to pull the graphic novels from the "Dungeon" series while it reviews them for appropriateness.

The board says it will contact CTV News once the review is complete.

With files from CTV Atlantic's David Bell