For Thea Bisenberger-van der Wal, Japan is a nation that took "our childhood away, raped our mothers and worked our fathers to death" during World War II, but is still refusing to come to terms with its wrongful past.

Bisenberger's late mother was one of tens of thousands, perhaps hundreds of thousands of women historians say were forced into sexual slavery for Japan's World War II soldiers.

Most of those sex slaves, euphemistically called "comfort women." were from Korea and China but at least 65 of them were Dutch women who stayed in Indonesia, then a Dutch colony.

Bisenberger says she will never forgive Japan until it acknowledges and rectifies its wrongful past.

"What I want from Japan is a confession for what their Japanese military has done to all these young girls and young women whose lives were ruined," she said, speaking about the suffering of her mother, forced into sexual servitude.

"Take the blame and remove the shame. Japan, it will haunt you forever. If you think that it will go away over time, you are wrong," the 73-year-old Bisenberger, who now lives in Canada, said in a recent email interview with Yonhap News Agency.

Bisenberger has been working to raise awareness of Japan's wartime atrocities since 2009, when she learned what her mother went through in the final years of World War II. Her family was in Indonesia, then a colony of the Netherlands.

She also wrote a book, "I Thought You Should Know," about her mother's experiences.

Bisenberger said her family was moved to a concentration camp after Japan invaded Indonesia. That's when her mother, then 24, was forced into sexual slavery for Japanese troops.

Her father was in a separate labor concentration camp and died there in 1943.

"I was one and a half when we were locked up and spent my first childhood years in filthy camps, always being hungry," she said.

"Japan took our childhood away. They raped our mothers, they worked our fathers to death, and they should get punished for it."

Bisenberger said her mother, Sietske van der Wal-Sijtsma, and one of her mother's sisters were raped at a Catholic church that Japan used as a brothel for its troops.

But her mother, who died in 2003 at age 84, never spoke to her about her ordeal. Bisenberger said she learned of it from an aunt, she said.

"After the war, Japan prospered and the victims had to fend for themselves. The war was never over for them," Bisenberger said.

"She kept it all inside. I think she was lucky to have a sister who had gone through the same with her, and with her they talked it about very often."

The "comfort women" issue is still pending in relations between South Korea and Japan. South Korea is urging Japan to resolve the grievances, saying the issue is becoming increasingly urgent as most victims are well over 80 and may die before they receive compensation or an official apology.

But Japan has claimed that all issues related to its colonial rule of the Korean Peninsula were settled through a 1965 treaty that normalized their bilateral ties. Seoul and Tokyo have held three rounds of director-general level negotiations on the issue this year, but little progress has been made.

Bisenberger said she admires Korean victims for their bravery to come forward.

"I urge them to maintain their stand and insist for recognition. This should never be forgotten, this painful past. I hope that no other country ever gets away unpunished with all the atrocities which Japan inflicted on innocent people," she said.

Bisenberger said she will "keep fighting and writing about the atrocities the Japanese military inflicted on innocent people until Japan recognizes that their past has to be rectified."

"The women who were there are getting older. Even we, the children, are in our late seventies, but our children and their children will remind Japan about their past," she said. "I hope that one day, we will come to a solution, so my mother and her sister can rest in peace." (Yonhap)