"It's hard to fathom the pain the victims must have suffered", Judge Kang Seong-soo ruled.
Known as molka, South Korean spycam videos are largely made by men secretly filming women in schools, toilets and elsewhere, although the term can also be applied to clandestinely shot footage of consensual sex.
K-pop star Jung Joon-young arrives to attend a hearing on his arrest warrant at the Seoul central district court in Seoul on March 21, 2019.
"Jung argued that his sexual act was done with mutual agreement, while Choi flatly denied having sex with the victims".
The court in Seoul also sentenced K-pop singer Choi Jong-hoon to five years behind bars for his involvement in the crime.
Goo's ex-boyfriend last year threatened to "end her entertainment career" by leaking the footage after they split up last year, and a CCTV clip showed her kneeling before him apparently begging him not to.
And now, eight months later, it's determined he and Choi will spend a few years' each in prison to atone for some of the horrors that they've perpetrated upon innocent women.
Jung and Choi both wept as the sentences were announced and claimed they had engaged in consensual sex with sober women. The two received six years and five years respectively, and will also be required to take 80 hours of sexual violence education. Kwon Hyuk Jun (Girls' Generation's Yuri's older brother) received four years.
Lawyers for Jung and Choi could not be reached for comment.
"I deeply regret my foolishness and I feel great remorse", Jung said in his final remarks to the court.
He was sentenced to six years in prison.
The identities of the victims were suppressed to protect their privacy.
Prior to Jung's conviction, the Seungri scandal almost took down one of the largest pop music record labels in South Korea, YG Entertainment.
Officials investigating Seungri requested copies of his private communications, revealing the group text messages in which Jung shared his videos with other friends in the music industry.