South Korea has been battling a growing epidemic of so-called molka, or spycam videos – mostly of women, secretly filmed by men. But K-pop stars generally cultivate clean-cut images, and are actively promoted by the South Korean government as a key cultural export.

Many face tremendous pressure to look and behave perfectly in an industry powered by so-called “fandoms” – groups of well-organised admirers at home and abroad who spend enormous amounts of time and money to help their favoured stars climb up the charts and attack their perceived rivals.

With fortunes at stake, they have more to lose than most by being embroiled in a scandal, even after a wave of #MeToo accusations in the still socially conservative South Korea during the past year. Lee Moon-won, a popular culture critic in Seoul, said the multilingual Seungri – who has multiple business interests – was popularly seen as an “ideal cultural export”.

“Most of his fans would agree that Seungri is an exceptionally hard working star,” Lee said. “On top of his singing career, he somehow mastered Japanese and Chinese, which made him a very useful member whenever BigBang visited those countries. Learning two foreign languages while being a K-pop star is definitely not an easy thing.”

Seungri was interviewed by police at the weekend over accusations he lobbied potential investors by offering them the services of prostitutes at nightclubs in Seoul’s posh Gangnam district.

The 29-year-old is also linked to a police investigation into Burning Sun, a nightclub where he was a public relations director, where staff are alleged to have filmed women with hidden cameras and used alcohol and drugs to sexually assault them.

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Before the scandal, Seungri had been nicknamed the “Great Seungsby” after the protagonist of the F. Scott Fitzgerald novel The Great Gatsby for his good looks, his seemingly successful business and the lavish parties he had thrown.

“It’s ironic how Seungri and Gatsby turned out to have more things in common after the scandal broke,” Lee said. “Both have engaged in illicit and corrupt activities to gain fame and wealth.”

Reaction among BigBang fans has been divided, some expressing anger and disappointment, others disbelief and support. Some overseas admirers posted online photographs of flowers and a hand-written note saying: “I’ll wait for you on this flower road” – a BigBang lyric.

Another tweeted that they did not want to believe the accusation, adding: “I’m tired of all this and in pain. I admired Seungri for a long time and he made me smile in my worst days.”

But a group of South Korean fans called for his expulsion from the band, saying he had “significantly damaged the team’s reputation”.

For South Korean women’s activists, the scandal is unsurprising. As well as secretly filming women in schools, toilets and offices, “revenge porn” – videos men take of themselves having sex with their exes or partners filmed without the women’s consent – is believed to be equally widespread. In a society where patriarchal values are still deeply ingrained, circulation of such content can significantly damage a woman’s reputation.

According to Han Sol, an activist at Flaming Feminist Action, spycam videos have long been watched and shared by South Korean men as a form of entertainment and a way to strengthen their “brotherly ties”.

Last year, Seoul several times witnessed thousands of women protesting against spycam vidoes as part of the country’s ongoing #MeToo movement.

“This case just shows that male K-pop stars are no exception when it comes to being part of this very disturbing reality that exploits women,” women’s rights activist Bae Bok-ju said.