From BDSM to threesomes, many people have sexual fantasies that they would love to make a reality. 

Now, a scientist has lifted the lid on one of the more unusual sexual fetishes he's come across. 

In his new book, Dr Mark Griffiths, a professor of behavioural addiction at Nottingham Trent University, has delved into 'toonophlia' - the sexual fetish for cartoons. 

'While researching the furry fandom (i.e, individuals who derive sexual pleasure from dressing up as an animal and/or derive sexual pleasure from having sex with someone dressed as an animal) and objectum sexuality (ie, individuals who develop deep emotional and/or romantic attachments to specific inanimate objects or structures), I kept coming across various online references to toonophilia,' he explained. 

'Toonophilia is a paraphilia in which individuals are sexually and/or emotionally attracted to cartoon characters including Japanese anime characters.'

Sexualised characters such as Lara Croft, Jessica Rabbit, or Hercules might be the first to spring to mind. 

However, Dr Griffiths says that he has encountered toonophiles who are sexually attracted to somewhat more unusual cartoons. 

This includes Bugs Bunny, The Flintstones, and even Ms Pac-Man. 

Writing in his book, Sexual Perversions and Paraphilias: An A to Z, Dr Griffiths explains that there are several different definitions for toonophiles online. 

'Some claim that toonophilia only applies to individuals whose primary or exclusive sexual interest is in cartoon characters. 

'There also appear to be other similar paraphilias, such as ficto-philia, in which individuals are romantically and/or sexually attracted to fictional characters in books and gameophilia in which individuals are romantically and/or sexually attracted to fictional videogame characters, such as Tomb Raider's Lara Croft.

'One (now defunct) website claimed that toonophilia is seen as a lifestyle and that "due to the absence of physical contacts between humans and cartoon characters" most toonophiles sexual activity, unsurprisingly, consists of masturbation.'

While this third definition points out the physical absence of cartoon characters, that hasn't stopped some toonophiles from pursuing relationships further. 

'At the Go Petition website there was a genuine petition asking for relationships and marriages between humans and cartoon characters to be made legal,' Dr Griffiths said. 

According to the expert, the most popular characters amongst toonophiles are Japanese anime characters. 

However, Dr Griffiths has also come across toonophiles who are attracted to Bugs Bunny, Ms Pacman, Jessica Rabbit, and Betty Boop. 

'Other sites feature obscene and/or pornographic images and videos of many different cartoon characters like The Flintstones having sex,' he added.

Unsurprisingly, Lara Croft is also a top choice for many toonophiles. 

'She's a big-breasted digital icon,' Dr Griffiths said. 

'However, most Tomb Raider players are not lusting adolescents.'

As part of his own research, Dr Griffiths questioned a group of players on why Tomb Raider is such a good game.  

'The single most important factor appeared to be the problem-solving component as part of the treasure hunt genre,' he explained. 

'Her physical attributes did not seem to be important for most players apart from the youngest teenagers. 

'Maybe it is among this group of teenage videogame players that toonophile tendencies might begin to develop.'

You can find out more about paraphilias in Professor Griffiths' new book, Sexual Perversions and Paraphilias: An A-Z.