So-called camouflage rapist Troy Johnson has been handed a 28-year prison sentence for abducting then sexually assaulting a 12-year-old schoolgirl on the NSW Central Coast.

NSW District Court Judge David Wilson said the mechanic and father-of-three had engaged in "truly evil conduct".

In the video above: father of woman who developed multiple personalities to cope with his abuse will die in jail

Wilson, who lifted the suppression order on naming Johnson, said the girl "was truly a victim of the detestable conduct of the perverted offender".

Johnson was jailed for 28 years with a minimum of 21 years.

The pig hunter was given the moniker because he disguised himself in a ghillie - a head to foot leafy military camouflage suit - to stay hidden as he stalked his young victim.

Johnson, who worked as an NBN contractor, also groomed and assaulted an 11-year-old girl for 18 months.

Knifepoint attack

He pleaded guilty to a total of 10 charges - seven offences involving the rape of the 12-year-old girl on May 15, 2017, and three offences involving the grooming and sexual abuse of another girl, aged 11, between August 2016 and April 2017.

Johnson grabbed the then 12-year-old from behind and dragged her into bushland as she made her way to school on the Central Coast in May 2017.

She had been walking along a track when she looked back and saw him suddenly emerge from the bushes armed with a large tree branch and a knife.

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When she pleaded "Stop, stop, stop", he put her in a headlock and forced her into the scrub.

Johnson told her: ''Don't scream or I'll have to hurt you."

After he released her, the girl ran to school and Johnson made his way to work.

When Johnson arrived at work about 9.30am, he told his co-workers - who had been unsuccessfully trying to get in touch with him - that he was covered with dirt and leaves because he had been involved in a road rage incident.

He claimed to have chased the other driver into the bush and fallen down an embankment.

Chevron Right Icon 'Hey dude, you'll never guess what I did.'

The judge said after raping the girl, Johnson called a friend and told him, "Hey dude, you'll never guess what I did."

He then boasted about his vile act.

No remorse

Johnson claimed he deserved a lesser sentence because he had been of good character before the rape.

But Wilson rejected the claim, after it was discovered Johnson had hidden a video camera in his family home since 2009 to film unsuspecting women in the bathroom.

Wilson also pointed out Johnson had stalked the schoolgirl for weeks before carrying out his plan to attack her.

Lied to psychiatrist

The judge believed Johnson had lied to his psychiatrist after his arrest when he claimed the attack was out of character, he did not know why he had done it and blamed the devil.

Judge Wilson had warned him that, because he was too cowardly to enter the witness box to express remorse and admit his paedophilic behaviour, and because of the devastating impact it had had on his victim, his jail sentence would be harsh.

Look at victim

Last week, Wilson ordered Johnson to look at his now 14-year-old victim as she told the court of the knifepoint attack he forced her to endure on her way to school.

In tears, she gave the terrifying account.

But details were suppressed to avoid adding to the teen's distress.

Chevron Right Icon 'You have shown immense courage.'

One she was finished, Wilson praised her courage.

"To come face to face with evil … you have shown immense courage," he said.