Judge Kevin Glubb lifted the sisters' automatic name suppression when they said they wanted to encourage other people who have been abused to speak out.
"Automatic name suppression makes you feel like you have to be hidden and ashamed," said Celeste, who was only 12 when Manamana began six years of offending against her.
"I wanted to show that it is not an embarrassment to have your name out there on this type of offence."
She said it was an empowering experience.
"From the experience of being abused, I lost so much: The relationship with my family, I lost my self respect, I lost my personality of being cheerful and carefree.
"Now I am gaining it all back.
"I really feel so much relief after talking about it and coming out, I feel brave and confident and well supported by everyone around me - it feels so empowering."
Tiana, who was abused from the age of 15, said the process had helped her heal from the abuse.
"Honestly for me it has made me a stronger person as going through healing has tested my strength.
"It has been hard coming to terms that it wasn't my fault and I shouldn't be ashamed but ... I tell myself nothing will be as hard as the abuse he put me through."
She echoed her sister's comments of the process giving her empowerment.
"I'm finally allowed to speak after the many years, since 15, of having to keep this secret. I feel content with myself knowing there is now nothing to hide."
Since the sisters' story was published today, other victims have already come forward, said Celeste.
"I have realised that it happens so much and people feel the exact same way, so I was thinking, 'Why is it like this?'
"It's got nothing to do with [the victim], they haven't put themselves in this position or done this to themselves.
"We are getting comments and messages from people already who are standing up for themselves, and that's why we have done this."
Judge Glubb told the court because Manamana had shown no remorse for his behaviour, there could be no reduction in his sentence of 16 years, reported Radio New Zealand.
Manamana will serve a minimum non-parole period of eight years.