Police claim Kalevi Paju, 59, presents a "serious risk to the health and sexual safety of children in the community" and fear he will continue to prey on vulnerable victims after blatantly ignoring his legal responsibilities as a registered sex offender.

The court heard Paju was placed on the NSW Child Protection Register (CPR) in November 2019 after being convicted of four counts of inciting a child under 16 to carry out a sexual act.

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He was released from prison on December 15 and told he must attend Wollongong Police Station within seven days to provide officers with a list on information including his address, telephone number, any social media accounts and/or internet access and affiliation with clubs involving children.

However, police claim said Paju ignored the orders and had made no attempt to contact anyone at the police station.

Meanwhile, Paju's parole supervisor contacted police on December 23 telling officers they'd discovered some disturbing material at his house during a home visit after Paju had failed to show up for a scheduled appointment.

Police attended his Smith Street home on Boxing Day, at which time they discovered a document titled "100 Ways To Praise A Child" pinned on the back of his front door.

When asked why he hadn't reported his details to police, Paju initially said he'd seen his parole officer then claimed to not know where the police station was situated.

"He said 'I only have to report to my people, I don't have to tell you anything, it's none of your business'," police wrote in court documents.

"When asked who his 'people' were, he replied 'parole'."

Paju was charged with failing to comply with his CPR reporting obligations and remanded in custody.

He pleaded guilty to the charge in Wollongong Local Court last week.

Police outlined Paju's history of inappropriate sexual interactions in the community, particularly with children,

The court heard he had two charges on his record for obscene exposure after flashing his penis to cafe staff in 2003, then masturbating in front of children at a playground in 2013.

In the latter incident, police found a handwritten note in Paju's pocket saying "I want to pick up a girl, display my goods to her so I could take her home, sustain an erection, make love and have [a] baby or babies because I'm a shy guy".

Paju also sexually propositioned two children in separate acts in 2017 and 2018.

Most of the charges have been dismissed under mental health legislation.

Meanwhile, police have revealed they hold grave concerns for the safety of the community when Paju is at large.

"Police hold fears [Paju] is going to continue, or escalate, the sexual behaviour towards children and people in the community," detectives wrote in documents tendered to the court.

Paju remains behind bars and will be sentenced on March 17.