Controlling a boy in a degrading way for his own sexual gratification, Mark Alvin Aquino made threats to force him to follow explicit rules.
Judge Michael Burnett delayed sentencing Aquino on Tuesday, calling for a psychiatric assessment to help determine whether the community needs lifetime protection from the 39-year-old.
The judge said he had seen nothing in his time in court like the behaviour outlined in the 33-page statement of facts about Aquino's offending.
"It's a very dark chapter in somebody's life," he said.
"I couldn't help but think that there was something wrong with this man that he could do this - behave in such a sinister and manipulative way."
Aquino pleaded guilty in the Brisbane District Court to 83 charges, some relating to a 14-year-old boy he pursued before gradually forming a relationship with another who was aged 11 when they met.
The charges included maintaining an unlawful relationship with a child, indecent treatment of children, grooming and threats.
Aquino was able to exercise coercive control especially in the last 12 months having already built up their connection over about two-and-a-half years, crown prosecutor Mark Green told the court.
He forced the child to follow complex rules like sexual acts they would perform, complying with sexual requests without question, allowing "sneakies" or touching of genital areas in public and sending two to three sexually explicit photos in specific poses daily.
The boy was required to message numerous times daily with details of his whereabouts, told to cut his hair in a certain way and received abusive messages about going out without permission.
"It was in that way (with rules) that the defendant exercised total control over the child," Mr Green told the court, saying the rules made the boy a tool for Aquino's sexual gratification.
If the child didn't comply, Aquino threatened breaking up by going to the boy's home, cutting off the boy's penis and testicles, killing him and taking his own life.
Aquino told the child to say goodbye to family and friends, that his own wife would be a widow and that he was ready to die.
"It is clear … the threats were of a sufficient nature to leave the complainant in a position where he believed he had no control over the situation and he had to comply with the defendant's directions," Mr Green said.
The boy courageously phoned Crime Stoppers when Aquino threatened to kill the child before taking his own life.
Aquino's wife told police about a second phone - containing videos featuring the boy that amounted to child exploitation material - hidden in his car when officers searched his house in November 2021.
Aquino, who has been in custody since the day of the search, was a calculated child sexual predator, Mr Green told the court.
He targeted a younger child after failing with the first boy and exercised an extreme level of coercive control for at least a year having worked out how to be a successful predator with a friendly face, Mr Green added.
Aquino's barrister James Godbolt is due to make submissions when the sentencing hearing continues.
The case will be listed for mention on April 1.
1800 RESPECT (1800 737 732)
National Sexual Abuse and Redress Support Service 1800 211 028
Lifeline 13 11 14
