NEW YORK, NY - SEPTEMBER 15: Singer Sulli attends Tory Burch Spring 2016 at Avery Fisher Hall at Lincoln Center for the Performing Arts on September 15, 2015 in New York City.  (Photo by Cindy Ord/Getty Images for Tory Burch)
PHOTO: Cindy Ord/Getty Images North America
NEW YORK, NY - SEPTEMBER 15: Singer Sulli attends Tory Burch Spring 2016 at Avery Fisher Hall at Lincoln Center for the Performing Arts on September 15, 2015 in New York City. (Photo by Cindy Ord/Getty Images for Tory Burch)
Now playing
00:48
K-pop star found dead in her home
Attorney-General Christian Porter speaks during a media conference on March 03, 2021 in Perth, Australia. Attorney-General Christian Porter has publicly confirmed he is the cabinet minister named in a historical rape allegation from 1988 which came to light in the last week and has emphatically denied the allegations.
PHOTO: Paul Kane/Getty Images
Attorney-General Christian Porter speaks during a media conference on March 03, 2021 in Perth, Australia. Attorney-General Christian Porter has publicly confirmed he is the cabinet minister named in a historical rape allegation from 1988 which came to light in the last week and has emphatically denied the allegations.
Now playing
02:25
Australian Attorney General denies historical rape allegation
Now playing
03:08
Cuba aims to produce its own Covid-19 vaccine
Police shoot stun grenades at Arab Israelis protesting an increase in gang violence in their towns.
PHOTO: CNN
Police shoot stun grenades at Arab Israelis protesting an increase in gang violence in their towns.
Now playing
04:18
Police shoot stun grenades at peaceful Arab-Israeli protesters
Mount Sinabung in Indonesia erupted on March 2, launching a cloud of ash and dust several kilometers into the sky. No one was injured in the eruption but authorities have warned people to stay away from the crater.
PHOTO: olcanological Survey of Indonesia via Reuters
Mount Sinabung in Indonesia erupted on March 2, launching a cloud of ash and dust several kilometers into the sky. No one was injured in the eruption but authorities have warned people to stay away from the crater.
Now playing
00:40
See this volcano in Indonesia erupt
New satellite images taken by Maxar show that North Korea sometime in the past year built a structure that may be intended to obscure entrances to an underground facility where nuclear weapons or nuclear weapons components are stored.
PHOTO: Courtesy Maxar
New satellite images taken by Maxar show that North Korea sometime in the past year built a structure that may be intended to obscure entrances to an underground facility where nuclear weapons or nuclear weapons components are stored.
Now playing
01:47
See images US intelligence claims is a secret weapons site
nigeria kidnapped schoolgirls released Busari pkg intl ldn vpx_00000423.png
nigeria kidnapped schoolgirls released Busari pkg intl ldn vpx_00000423.png
Now playing
02:09
Tears of joy and relief as 279 Nigerian schoolgirls return home
Protesters take cover behind homemade shields as tear gas is fired during a demonstration against the military coup in Yangon on March 1, 2021. (Photo by STR / AFP) (Photo by STR/AFP via Getty Images)
PHOTO: STR/AFP/AFP via Getty Images
Protesters take cover behind homemade shields as tear gas is fired during a demonstration against the military coup in Yangon on March 1, 2021. (Photo by STR / AFP) (Photo by STR/AFP via Getty Images)
Now playing
02:16
Footage shows tear gas, flash bangs used on protesters in Myanmar
01 rivers migrants pkg 02282021
PHOTO: CNN
01 rivers migrants pkg 02282021
Now playing
04:41
CNN correspondent speaks to migrants making dangerous journey to US
PARIS, FRANCE - MARCH 01: Former French President Nicolas Sarkozy leaves court after being found guilty of corruption and influence-peddling on March 01, 2021 in Paris, France. Mr. Sarkozy is only the second French president in modern times to have been convicted, after the conviction of former President Jacques Chirac in 2011.  (Photo by Kiran Ridley/Getty Images)
PHOTO: Kiran Ridley/Getty Images
PARIS, FRANCE - MARCH 01: Former French President Nicolas Sarkozy leaves court after being found guilty of corruption and influence-peddling on March 01, 2021 in Paris, France. Mr. Sarkozy is only the second French president in modern times to have been convicted, after the conviction of former President Jacques Chirac in 2011. (Photo by Kiran Ridley/Getty Images)
Now playing
03:23
'An earthquake in French politics': CNN reporter on Sarkozy sentence
PHOTO: Isaac Abrack
Now playing
03:00
Hear from schoolgirl who escaped abduction in Nigeria
UK police appealed for help Friday, Feb. 20, 2015, to find three teenage girls who are missing from their homes in London and are believed to be making their way to Syria.

The girls, two of them 15 and one 16, have not been seen since Tuesday, Feb. 17, 2015, when, police say, they took a flight to Istanbul. One has been named as Shamima Begum, 15, who may be traveling under the name of 17-year-old Aklima Begum, and a second as Kadiza Sultana, 16. The third girl is identified as Amira Abase, 15.
PHOTO: Metropolitan Police
UK police appealed for help Friday, Feb. 20, 2015, to find three teenage girls who are missing from their homes in London and are believed to be making their way to Syria. The girls, two of them 15 and one 16, have not been seen since Tuesday, Feb. 17, 2015, when, police say, they took a flight to Istanbul. One has been named as Shamima Begum, 15, who may be traveling under the name of 17-year-old Aklima Begum, and a second as Kadiza Sultana, 16. The third girl is identified as Amira Abase, 15.
Now playing
00:39
Shamima Begum loses legal bid to return home to appeal citizenship revocation
PHOTO: Obtained by CNN
Now playing
08:29
How a religious festival turned into a massacre
Saudi Crown Prince Mohammed bin Salman attends a conference in the Saudi capital Riyadh on October 2018.
PHOTO: FAYEZ NURELDINE/AFP/Getty Images
Saudi Crown Prince Mohammed bin Salman attends a conference in the Saudi capital Riyadh on October 2018.
Now playing
02:10
US intel report: Saudi Crown Prince responsible for approving Khashoggi operation
A Fijian rugby team serenaded workers in the Sydney hotel where they are quarantining.
PHOTO: Costa Argyrous
A Fijian rugby team serenaded workers in the Sydney hotel where they are quarantining.
Now playing
00:45
See Fijian rugby team serenade quarantine staff in Australia
Soldiers stand guard outside the CRS Turi prison in Cuenca, Ecuador on February 24, 2021. - At least 79 inmates died in simultaneous riots blamed on gang warfare at four prisons in Ecuador, officials said Wednesday. (Photo by FERNANDO MACHADO / AFP) (Photo by FERNANDO MACHADO/AFP via Getty Images)
PHOTO: FERNANDO MACHADO/AFP/AFP via Getty Images
Soldiers stand guard outside the CRS Turi prison in Cuenca, Ecuador on February 24, 2021. - At least 79 inmates died in simultaneous riots blamed on gang warfare at four prisons in Ecuador, officials said Wednesday. (Photo by FERNANDO MACHADO / AFP) (Photo by FERNANDO MACHADO/AFP via Getty Images)
Now playing
01:54
Ecuador prison riots leave dozens dead in gang 'extermination'
(CNN) —  

She was one of only a few celebrities to be publicly pro-choice when South Korea legalized abortion this year, was open about her own mental health struggles and insisted women shouldn’t have to wear bras if they found them uncomfortable.

Those actions won 25-year-old K-pop singer Sulli praise – but also made her the subject of harsh online criticism.

Now, a day after her apparent suicide, her death has prompted an outpouring of grief and calls to curb the cyber-bullying stars can be subject to when they stray outside the K-pop industry’s traditional norms.

Pictures of Sulli posted on her Instagram.
PHOTO: instagram/jelly_jilli
Pictures of Sulli posted on her Instagram.

The body of the former member of girl group f(x) was discovered by her manager in her house in Sujeong-gu, Seongnam, south of the capital Seoul, on Monday afternoon local time, police told CNN. In a statement Tuesday, Sulli’s agency SM Entertainment said the star’s family was planning a private funeral, adding that relatives were “grief-stricken by this unexpected sad news.”

According to the Seongnam Sujeong Police, a postmortem could be conducted as early as Wednesday. News of her death had an instant impact across the industry, with other SM Entertainment groups Super Junior and SuperM, as well as former f(x) bandmate Amber Liu, all announcing they would cancel upcoming events.

From being candid about her own relationships – unusual in the world of K-pop, where stars are encouraged to keep quiet about romance – to being openly pro-choice and an advocate of the “free the nipple” movement, Sulli was known for subverting expectations of female K-pop stars.

But her opinions often made her a target of online trolls, particularly by anti-feminists, said CedarBough Saeji, an expert in Korean culture and society at Indiana University.

“She was brave,” Saeji said on Tuesday. “The fact that Sulli repeatedly did things that misogynists didn’t like, and refused to apologize, is how she really stood out.”

Saeji said that in South Korea, K-pop stars were expected to apologize publicly when they failed to meet the high – and sometimes unrealistic – standards expected by the industry. But Sulli refused to change, even appearing on a TV show that featured K-pop stars discussing the challenges of negative online comments.

“That society would criticize her so heavily just for showing individuality in a way that did not conform exactly to Korean social norms, that’s just so incredibly sad,” Saeji said.

Singer Sulli attends Tory Burch Spring 2016 at Avery Fisher Hall at Lincoln Center for the Performing Arts on September 15, 2015 in New York City.
PHOTO: Cindy Ord/Getty Images North America
Singer Sulli attends Tory Burch Spring 2016 at Avery Fisher Hall at Lincoln Center for the Performing Arts on September 15, 2015 in New York City.

“I’m so sorry that she didn’t have people supporting her in the same way that she was supporting – in her own quirky way – gender equality in Korea. She was also being a voice, and being a proponent, for larger issues in Korean society.”

As of Tuesday, three petitions had been lodged on the Blue House petition site, all demanding tighter rules for cyber-bullying.

South Korea’s entertainment industry has become one of the country’s biggest exports in the past decade. But K-pop stars – who often train for years before they debut – are subject to intense pressure, which has been linked to a mental health crisis in the industry.

K-pop megastar Jonghyun, whose real name was Kim Jong-hyun, took his own life in Seoul in December 2017. And singer and actress Goo Hara, formerly part of girl band Kara, apologized to fans after being found unconscious at home in May 2019.

The singer had posted the word “Goodbye” to her Instagram account, prompting a flood of comments from concerned fans.

How to get help: In the US, call the National Suicide Prevention Lifeline at 1-800-273-8255. The International Association for Suicide Prevention and Befrienders Worldwide also provide contact information for crisis centers around the world.

Yoonjung Seo and Shin Jae-eun reported from Seoul, South Korea, and Julia Hollingsworth wrote from Hong Kong.