The full decision is expected to be released this week.
At the time of the attacks — between October 2009 and July 2012 — Nixon was involved in outdoor dance events.
Many of the victims were friends of his then girlfriend.
He attacked them as they slept or when they were drowsy or under the influence of alcohol or drugs.
He admitted 13 charges in court — six counts of rape against five women, three counts of sexual violation, two counts of sexual connection with a person aged under 16 and two counts of indecent assault.
It has been reported Nixon was autistic, which affected his ability to read social cues, but the Court of Appeal concluded in 2016 there was no evidence his assessment of consent by the complainants was affected by his disability.
The court did, however, shave a year off his jail sentence, to 13 years, and cut the minimum non-parole period from eight years to six-and-a-half years.
Another appeal — arguing Nixon could have offered a tenable defence based on his "reasonable belief" in consent, and that not enough allowance had been made in sentencing calculations for hardships he faced in prison as a result of his disability — was thrown out by the Supreme Court in 2017.
The Otago Daily Times was granted access to Wednesday's parole hearing by video link.
Nixon told the hearing he had developed a better understanding of his actions and what his victims had faced.
"I hope they find ways to do the best they possibly can," he said.
At his 2015 sentencing, victims provided harrowing accounts of how their lives had been changed by Nixon's offending.
One said she did not feel safe anywhere in the world and told the court she had been sentenced to a lifetime of flashbacks, panic attacks and counselling.
Another said her trust in men had been destroyed and she had developed an eating disorder.
Three of the complainants had contemplated suicide.
Nixon told the parole board his attitude to women had changed.
His relationships in the past had been based on sex, but future ones would be based on friendship, he said.
Nixon said he was learning how to interact with people better, including communicating effectively.
"I'm the one with the communication difficulties — I know that now."
Nixon's lawyer Michael Bott said his client had a tragic background.
His mother told the Dunedin District Court in 2015 he had suffered from "poor judgement", which was exacerbated by drug and alcohol consumption.
The parole hearing was told Nixon's behaviour in prison programmes had been exemplary.
Sexual harm - Where to get help
If it's an emergency and you feel that you or someone else is at risk, call 111.
If you've ever experienced sexual assault or abuse and need to talk to someone, contact Safe to Talk confidentially, any time 24/7:
• Call 0800 044 334
• Text 4334
• Email support@safetotalk.nz
• For more info or to web chat visit safetotalk.nz
Alternatively contact your local police station - click here for a list.
If you have been sexually assaulted, remember it's not your fault.
