Hana Kimura was found dead in her apartment in the early hours of Saturday. She had a plastic bag over her head and poisonous chemicals were circulating in her bedroom. Kimura left a note apologizing to her mother, adding, "Thank you for giving birth to me."

Known for her perky character and youthful naivete when she joined Terrace House, which is aired on Fuji TV and has attracted high viewer figures, Kimura started attracting negative comments on her social media outlets after a clash with a male member of the house. The man accidentally damaged one of Kimura’s prized wrestling costumes when he washed it and she reacted furiously, slapping him.

The backlash was quick and fierce; posters on Twitter and other social media sites demanded that she immediately leave the reality TV show and accused her of being "stupid." More than one post said Kimura should kill herself.

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Stars express support

"How can you judge people you have never met and only seen on screen?" messaged Ryo Tawatari, a basketball player who left the Terrace House set earlier this year, in a post aimed at Kimura's online assailants.

"Did they do something directly to you that you didn't like? What do you know? Are you perfect? You don't know the thoughts every individual has as they live their lives. You don't know their anxieties," he added. "You don't know if they have a past. Before you talk about other people’s lives, live your own life."

Reina Triendl, a presenter of the show, added in an Instagram post, "I wonder whether it is possible for all of us, off-line and especially also on-line, to create a kinder, more loving world in which we do not hurt or damage others, even inadvertently."

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Other people on the show also appear to have been the target of similar online attacks, with an Instagram post by Emika Mizukoshi saying she had also been abused.

"When I left Terrace House, I was also hurt by slander," she wrote. "Lots of people wrote 'Die' or 'Go away' or 'Don't go on TV if you can’t handle it.' But even people who work in the spotlight are human."

"We have emotions. Words really become weapons," she added. "The problem is not that you are mentally weak or you can't hack it, or you're out there so you should just take it. We have to dispel this trend of thinking that it's OK to say anything you like to so-called famous people."

Makoto Watanabe, a professor of media and communications at Hokkaido Bunkyo University, said people who "hide behind" anonymous social media posts "are frustrated that they themselves have been excluded from these sorts of opportunities, they are jealous and they are just looking for an opportunity to attack someone."

The ferocity of the attacks on Kimura did come as a surprise, Watanabe admitted, as did the sheer number of people joining in.

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New levels of intolerance

"I have the impression that we are seeing a new trend of intolerance towards diversity, which means that anyone who is 'different' can quickly become a target," he told DW. "Sadly, it could be argued that our society is simply not ready or able to deal with the technology that we now have, and too many people do not comprehend the full consequences of what they are doing."

Kyle Cleveland, a professor of Japanese culture at the Tokyo campus of Temple University, also admits to being shocked at the vicious nature of the attacks on Kimura.

"In a society that has such a reputation for respect and public decorum, of being well-mannered and principled, people who are unleashed on the internet have become totally unrestrained," he said. "There is no accountability and people are free to be very belligerent. It can be really brutal."

The situation with online abuse in Japan is now rivaling the high-pressure existence of stars of the music and acting worlds in South Korea, Cleveland pointed out, where K-pop star Sulli killed herself in October, followed the next month by singer Goo Hara. Both suicides were at least in part blamed on cyber-abuse and trolling.

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Under pressure

Under pressure from TV companies to keep ratings for shows high, management to keep working harder and fans with access to 24-hour social media, Cleveland says the pressure must be excruciating – particularly for young people with little understanding of what they have got themselves into and no-one trustworthy to turn to.

"To me, Kimura seemed pretty psychologically vulnerable, and that would have been made worse by the fan culture that has reached the point where it is almost as if these people live in a state of permanent surveillance," he said.

Watanabe believes that if there is anything positive that can be taken from the death of a young woman under pressure from faceless critics, it is that at least Japan is now having a discussion about suicide.

"Too often we see cases in the papers about schoolchildren who commit suicide because they are being bullied via social media," he said. "Now the television shows are talking about Kimura, about what she had to put up with, and there is this new awareness of bullying and suicide.

"Maybe this conversation will make people more aware of the impact that their words can have."

If you suffer from emotional strain or suicidal thoughts, please seek professional help. You can find information on where to find help, no matter where you live in the world, at befrienders.org