Ayden Devereux enthusiastically encouraged his friends to continue gang raping a drunk teenage girl at a Sydney party as he filmed the "revolting acts" on a GoPro camera.
"Let's go, who's up?" Devereux says in the footage, which shows a group of men having sex with the 16-year-old at a house party at St Clair in May 2015.
"One by one we'll all get a f***," he says.
Devereux, 26, on Wednesday was jailed for seven-and-a-half-years with a non-parole period of five years after pleading guilty to two counts of aggravated sexual assault in company.
"The offending behaviour is disgraceful," Judge Christopher Hoy said at the Downing Centre District Court.
The victim, a "shy and awkward" girl with an intellectual disability, was invited to the party after befriending Tristan Carlyle-Watson on Facebook.
She became so drunk she has no memory of what unfolded.
The graphic 17-minute video shows the men lining up to take turns sexually assaulting the girl who at times appears motionless.
Devereux, holding the camera, is heard urging them on.
"This offender spouted words of demeaning vulgarity and crudity," Judge Hoy said.
"His commentary suggests increasing and ongoing enthusiasm."
Devereux didn't touch or sexually assault the victim but he was present while others did and at no point did he intervene or assist the victim, Judge Hoy said.
He said the "revolting acts may never have seen the light of day" had police not uncovered the GoPro footage while investigating an unrelated matter six weeks later.
In sentencing Devereux, Judge Hoy took into consideration his good record, relatively young age and genuine remorse.
"These charges I suspect have been the biggest shock of his life," he said.
"It is so sad that he now faces this predicament not only for him but for those who care for him."
Devereux will be eligible for parole in October 2020.
A jury in August found his co-offenders - Carlyle-Watson, Kurt Stevenson and Andrew Waters - guilty of aggravated sexual assault in company.
The trio is due to face a sentence hearing on October 27.