However, it is a boom in illegal "spycam" videos, filmed secretly in toilets, changing rooms and other public places and posted as pornography, that has provoked the most fury. Last month, more than 40,000 women protested in Seoul over what has become a major invasion of privacy in daily life.
"The fear towards spycams that many Korean women have felt has now turned to anger," said the organisers.
But as South Korean women revolt, they are also paying the consequences, according to the group.
They said: "Men were live-streaming the event on the internet by shooting videos of the protesters' faces. There were people on the internet claiming they will attack the protests with acid. There was even a case where a man followed a protester to the house, screaming about why she was taking part in such protests."
The number of reported spycam crimes has surged from around 1100 in 2010 to more than 6500 last year.
The group said the police and government had not addressed the problem seriously enough.