Documentary support

Zhang Jindong, a student majoring in film production, who is also studying Korean, approached the museum to apply for volunteer work.

He said he was moved by Twenty Two, a documentary on "comfort women" made with support from Su, who also serves as director of the museum and the university's Chinese "comfort women "research center.

"I was so touched by the 'grandmas' in this documentary. They are just like my own grandmother, who died recently," he said.

A total of 22 "comfort women "living on the Chinese mainland in 2014 were filmed for the documentary, which was crowdfunded by more than 32,000 people.

Released in 2017, the film has made a record 150 million yuan ($23.19 million) at the box office. Its director, Guo Ke, donated his earnings to set up a special foundation run by the university to support "comfort women" and research on the issue.

The film is a sequel to Guo's documentary Thirty Two, made in 2012, when there were 32 living Chinese "comfort women".

The two documentaries remain influential and are played online or at special screenings every year during International Memorial Day for Japanese Military "Comfort Women" on Aug 14.

In the past month, the film team has received orders worth 420,000 yuan for souvenirs related to the latest documentary. This money was donated to the 14 living victims.

When a "comfort woman" dies, Su publishes an obituary of her on his research center's website and attends the funeral.

According to his studies over the past three decades, some 400,000 women in Asia, nearly half of them Chinese, were forced to serve as "comfort women" for the Japanese military during World War II.

"As far as we know, there are only 14 surviving 'comfort women'on the Chinese mainland," he said, adding that their average age is more than 90.

"We are losing them almost annually," said Su, who visits the survivors with his students every year, taking notes, documenting the women's histories and providing care and companionship.

In the past 30 years, Su and his team have published many books and papers on the issue. One of their most recent books, Evidence: Revealing 172 Comfort Stations in Shanghai, was published in 2018.

"When I started my studies in 1993, I thought there were only four to six 'comfort stations' in Shanghai, but now my research presents evidence that at least 172 such stations were established in the city," Su said.

The book provides detailed locations, historical photos and related information about Japanese military brothels, with a wealth of evidence from Japanese government archives and Japanese soldiers' memoirs.

"Shanghai was where the Japanese built the most 'comfort stations' in the world, which victimized tens of thousands of Chinese and Korean women, with many of them losing their lives," Su said.

He has helped other cities launch similar comprehensive research to collect evidence of wartime "comfort stations". Two years ago, Su spent 20,000 yuan on a small photo at an auction in Tokyo. The photo showed several Japanese soldiers leaving a house in Nanjing, where signs indicated it was a brothel.

Su said he hasn't found the location of the building, but he suspects it was one of the "comfort stations" built by the Wang Jingwei Puppet Regime of the Empire of Japan from 1940-45.

"There are fewer and fewer survivors, but the Japanese government still hasn't apologized, so the research must go on," Su said in his office overlooking the sculpture of the Korean and Chinese peace girls at Shanghai Normal University.

On the empty chair beside the sculpture, a bundle of flowers was laid on Saturday. Words on the stone under the sculpture read: "We can forgive, but we can never forget."

Kim Do-hee contributed to this story.