A 3ft Japanese porn star who capitalises on looking like a child in X-rated films is actually a 24-year-old computer programmer.

Kohey Nishi, who has an incurable disease called mucopolysaccharidosis, earns a living by having sex with women who look old enough to be his mother.

He struggles to stand for longer than five minutes because of his condition, but added that this does not bother him as most of his porn shoots are on a bed.

Kohey Nishi, a 3ft Japanese porn star who capitalises on looking like a child in explicit films, is actually a 24-year-old computer programmer

Mr Nishi was introduced to the adult film industry by his 'drinking buddy', porn mogul Ganari Takahashi, and hopes to 'prevent children from being sexually abused' through his work.

The former computer programmer joins the likes of Bridget the Midget, Mini Mya and Lady Gangsta in carving out a niche for little people in porn.

The 3ft 6in star's disease halts growth and leaves him vulnerable to spinal cord injuries - meaning he cannot stand for longer than five minutes.

Mr Nishi, who also cannot open a plastic bottle or hear in his left ear due to his condition, had a 'miracle' bone marrow transplant which stopped the disease's development.

Despite his growing fan base, he admitted that the pressure can get to him and he struggles to sustain an erection in front of film crew.

Mr Nishi, who has an incurable disease called mucopolysaccharidosis, earns a living by having sex with women who look old enough to be his mother

He admitted that he finds it hard to sustain an erection in front of crew but added that his condition does not bother him as most porn shoots are done on a bed

He has been capitalising on his youthful look, which he says is huge with a younger audience and women.

'There is no one who is an adult and looks like a kid more than me!' he told Vice.

'You cannot cast actual kids sometimes [in non-pornographic content], so I'd like to fill the gap in that market.'

He added: 'I was once told that "Your videos seem dangerous as you look a real kid on screen."

'But I have considered that my works prevent children from being sexually abused, just like war movies and shooter video games can contribute to peace.'

Mr Nishi currently makes films with titles like 'Having Sex in the Magic Mirror Box Car with a Female College Student with F-Cup Breasts Who Wants to Be a Kindergarten Teacher.'

He admitted that he wants to move into American porn and non-erotic films in the future.

Mr Nishi was introduced to the adult film industry by his 'drinking buddy', porn mogul Ganari Takahashi, and hopes to 'prevent children from being sexually abused' through his work

The 3ft 6in star's disease halts growth and leaves him vulnerable to spinal cord injuries - meaning he cannot stand for longer than five minutes

Japan was the only member of the G7 group of industrialised countries that had not banned possession of child porn until 2014.

Until then, you could not make or distribute child porn, but you could possess it.

After the laws came into effect, anyone with child porn had one year to get rid of their collection.

However, paedophilic images remain legal in manga comic books and advocates insist banning such images would be a violation of their freedom of speech.

Michael Seto, a psychologist and sexologist at the University of Toronto, told The Atlantic there were two different types of paedophiles while talking about child sex dolls.

'For some paedophiles, access to artificial child pornography or to child sex dolls could be a safer outlet for their sexual urges, reducing the likelihood that they would seek out child pornography or sex with real children,' he said.

'For others, having these substitutes might only aggravate their sense of frustration.'