Pretoria - Convicted murderer Johan Kotze and his three co-accused were handed life sentences by the High Court in Pretoria on Wednesday.
"He seems inherently evil," Judge Bert Bam said of Kotze.
Kotze and Andries Sithole were sentenced to life imprisonment for the murder of Conrad Bonnette, 19. He was the son of Ina Bonnette, Kotze's ex-wife.
Both also got 10 years for kidnapping.
"It was a senseless act," Bam said.
Kotze and Sithole were found guilty on Monday of killing Conrad Bonnette.
Pieta Mohlake and Sello Mphaka were acquitted on the murder charge. However, each of the four was convicted of kidnapping, and of four charges relating to the rape of Ina Bonnette.
Mohlake and Mphaka received 10 years for kidnapping.
All four men were each given a life sentence on the rape charges.
For assault with intent to do grievous bodily harm, Kotze received 15 years, and the other three eight years each.
Ina Bonnette was attacked and tortured in Kotze's Modimolle home on January 3, 2012. Her son was shot and killed in the house on the same day.
Bam said there were three aspects which needed to be taken into account when deciding on a sentence. These were the nature of the crime, the personal circumstances of the accused, and the community's interests.
Bam said certain crimes, such as premeditated murder and gang rape, had a mandatory life sentence.
"Conrad's murder was planned. It was a pre-planned murder."
He said the accused's personal circumstances were less important than the aggravating factors in the case.
Conrad Bonnette was killed within earshot of his mother. Despite pleading for mercy, he was still killed.
"This contributed to Ina Bonnette's trauma."
He said she was badly injured and raped by a man she trusted, accompanied by three masked men.
"A more shocking and traumatic experience is unfathomable."
The trauma and humiliation she underwent would be difficult to describe, Bam said.
Her assault had to be seen in a serious light.
"The injuries were serious and also left her psychologically scarred," Bam said.
He briefly touched on the mitigating aspect of remorse during sentencing. Remorse could only act in mitigation of sentence, not in aggravation, he explained.
"However, in this case there was no sign of remorse from any of the accused."
There was no reason to deviate from the prescribed sentences. The aggravating circumstances in the case were overwhelming.
Bam said it appeared Kotze was excessively jealous over Ina Bonnette.
Bonnette, who was in court on Wednesday, started crying as the sentence was read out. She was supported by family and friends.
"A person just has to stand strong," she said after the sentencing.
She urged victims of abuse to report the crime and ensure they followed the right channels.
"Jesus put each of us on this earth for a purpose, and that purpose is not to abuse," Bonnette said.
"Justice has been done. (Kotze) deserves his sentence."
She said the sentencing marked the start of a new phase of her life.
"Time will heal the humiliation, but the hurt will never go away."
She said she would go to her son's grave and have a long talk with him afterwards.
"And I can tell him: 'My son, justice has prevailed.'."
Women, Children and People with Disabilities Minister Lulu Xingwana welcomed the sentence.
"Justice has been done," she said, holding Bonnette's hand.
"We hope that this sentence will bring closure and peace to (Bonnette) and her family to know that those who have violated her and murdered her son are finally behind bars," Xingwana said.
"We hope the monster and his co-accused will rot in jail."
After the sentence was handed down, family members of Kotze's co-accused cried. One woman started wailing.
Kotze declined to speak to the media and hurriedly made his way down to the cells. - Sapa