Tony Cronstam, 46, made his name penning iconic adult comics about the adventures of Elvis, an anthropomorphic turtle.
But after his three-year-old daughter started describing some of the playground humour at her kindergarten, he decided to launch a completely different kind of cartoon – designed to inform children about stripping off.
“She said the boys didn't want to play with her because of 'girl germs',” he tells The Local.
“I asked myself who is teaching children about these things? The tragic thing is that people think it's a joke but there is nothing harmless about placing thoughts in our young children's minds that are not based on equality.”
Cronstam's subsequent creation is a series of books featuring cartoon characters named 'Snopp' and 'Snipp', Swedish slang words for male and female genitals. The first was released in Sweden in September with the second due out later this month. The cartoonist is also hoping to achieve international success with an upcoming English translation, set to be called 'Willy and Nunny'.
“When it comes to our genitals there is a whole different acceptance of the male genitals to the female ones,” he argues.
“No one questions a small boy playing with his willy – some grown ups will laugh and say 'you'll have a lot of fun with that when you grow up' but I have never seen anyone making the same comments to a girl. It's more like 'oh-oh-oh, you shouldn't touch that',” he adds.
Image: Tony Cronstam
In the first book, Snipp and Snopp learn that they are both equal because they can both complete challenges such as picking up a worm and solving a maths problem.
Cronstam then takes his equality theme a step further, with the book's characters also discussing that some people who are born boys actually feel like they are girls and vice versa.
“We don't only have two sexes these days (…) I realized I needed to include that after showing the book to a friend of mine who was born without a willy,” he says.
“He is a man, but by society's norms [he] is not, just because of his genitals.”
The books are aimed at children aged between three and six.
Tony Cronstam. Photo: Peter X Eriksson
The writer, who is based in Malmö in southern Sweden, is not the first to grab headlines with cartoon depictions of genitalia this year.
In January, a video of dancing penises and vaginas produced by Swedish children's television programme Bacillakuten went viral, amid a global debate about Sweden's open approach to discussing sexuality.
Cronstam insists he had already submitted the manuscript for his first book to his publisher, two months before the video became a YouTube hit.
“The video didn't influence me at all,” he says.
“I just feel that kids are born complete and happy and then they get bombarded by the media and grown ups telling them about gender stereotypes (…) They should be free to be themselves and not feel ashamed about their bodies.”
The books are very different to Tony Cronstam's previous work. Image: Tony Cronstam