Cho Ju-bin ran a group that blackmailed women and girls, including minors, into filming and sending sexual content from May 2019 to February 2020.

The group illegally shared these images in pay-to-view chatrooms on messaging app Telegram, in a case that reignited a national conversation over how seriously hyper-connected South Korea handles digital sex crimes.

Critics have accused authorities of being too lenient on the widespread illegal sharing of sexual content.

South Korean women have also taken to the streets in protest over an epidemic of cameras hidden in toilets, schools and other places to secretly record them.

In 2020, Cho was sentenced to 40 years behind bars, with appeals courts later adjusting the term to 42 years and four months.

In a separate case, Cho was convicted of raping a minor and producing sexually abusive content without the victim's consent, and was sentenced to five years in jail by a lower court earlier this year.

The Supreme Court upheld that decision on Thursday -- dismissing Cho's appeal and confirming a total of 47 years and four months in prison for him.

Cho's appeal, which had argued that adding the five-year sentence would push his total prison term beyond the legal maximum of 45 years for combined offences, was rejected.

The issue of digital sex crimes has also impacted the country's showbiz industry.

In 2019, K-Pop star Goo Hara took her own life after being the victim of so-called revenge porn threats by an ex-boyfriend.

Another K-Pop star Jung Joon-young was jailed for five years after being convicted of filming and distributing sex videos without the consent of his female partners.