A heartbroken father spent six years and $500,000 in an international court battle to prove that his daughter's Japanese guru, a master of the 'dance of darkness,' turned her into a sex slave, plied her with drugs and was responsible for her suicide.

Tibor Stern filed a wrongful death lawsuit against Katsura Kan, who was teaching Butoh, a form of dance in which students were told to 'wallow in the darkness of their soul,' at a college in Boulder, Colorado, according to the lawsuit.

Kan, whose real name is Terugoshi Kotoura and is believed to be aged 71, was found liable last month for the suicide of his student, Sharon Stern, by a Florida circuit court. A trial will take place in a few months to determine the damages.

Tibor Stern, 70, of Hollywood, Florida, described his victory as 'bittersweet.'

'I thought it would bring much more closure,' he told DailyMailTV. 'I had no doubt we were going to win; the evidence was overwhelming. But I didn't jump for joy.'

'Our daughter is not coming back. But hopefully our effort will save some lives. That was the whole idea.'

Sharon Stern was driven to commit suicide in April 2012 aged 32 by her dance mentor Katsura Kan, who taught her Butoh, a form of dance in which students were told to 'wallow in the darkness of their soul,' according to the wrongful death lawsuit filed by her father Tibor Stern

Kan (pictured), whose real name is Terugoshi Kotoura, teaches Butoh, a dance that features slow, controlled movements and is traditionally performed in white body makeup, it also portrays grotesque imagery or absurd environments

Tibor, 70, (pictured with Sharon) of Hollywood, Florida, described the wrongful death victory as 'bittersweet.' He said: 'I thought it would bring much more closure. But I didn't jump for joy. Our daughter is not coming back. But hopefully our effort will save some lives. That was the whole idea'

Katsura Kan did not respond to requests from DailyMailTV for comment.

Sharon Stern, whom her family affectionately called 'Sharoni,' was beautiful and talented, with a lifelong interest in dance and performance, Tibor said.

After graduating from the University of Miami in 2001, Sharon performed as an actress and comedienne, taught yoga and was an avid swing and blues dancer.

Sharon married Todd Siegel, a software engineer, in May 2007. The couple moved to Boulder, Colorado, where Sharon enrolled in the master of fine arts program at Naropa University.

That's where Sharon encountered Katsura Kan, a Japanese citizen and guest artist who taught Butoh, the 'dance of darkness.'

This avant garde dance style features slow, controlled movements and is traditionally performed in white body makeup. Butoh dances often portray grotesque imagery or absurd environments, and explore taboo themes such as homosexuality and pedophilia.

'Under the guise of molding Sharon into a Butoh artist,' Tibor's lawsuit stated, Kan 'intentionally and/or recklessly inflicted emotional pain and suffering on Sharon continuously from the day he met her until the day she died.'

'We sent a totally happy girl, a pillar of the community, to college,' Tibor said. 'When she went to school, she respected teachers, respected authority. She wanted to excel in theater, and wanted to be a director. She was extremely talented. But she went to the wrong university and got the wrong teacher.'

After graduating in 2009, Sharon continued to work for Kan, organizing Butoh performances and festivals all around the world.

Kan, who was married and had a child, 'systematically stripped away Sharon's dignity, free will and self-respect,' the lawsuit claimed. He 'seduced Sharon, abused her physically and mentally, humiliated her, insulted her, and manipulated her.'

Sharon (far right) met Kan (center) when she enrolled in the master of fine arts program at Naropa University in Boulder, Colorado in 2007. This avant garde dance style features slow, controlled movements and is traditionally performed in white body makeup

Sharon Stern, whom her family affectionately called 'Sharoni,' was beautiful and talented, with a lifelong interest in dance and performance, Tibor said

'We sent a totally happy girl, a pillar of the community, to college,' Tibor said. 'When she went to school, she respected teachers, respected authority. She wanted to excel in theater, and wanted to be a director. She was extremely talented.' Pictured l-r: Tibor, Sharon's brother, Sharon and her mother Hana at her brother's wedding in 2010

Throughout her involvement with him, Kan solicited money from Sharon to use in his Butoh dance business, the lawsuit claimed.

'He told her to steal things and give him the money,' Tibor said. 'This honest girl who could not tell a white lie — she felt compelled to steal so she could give him the money.'

By 2010, Tibor began to suspect that Sharon was in a cult. Kan's group performed in Israel, where Tibor has family. His sisters-in-law went to see Sharon and noticed a total change in her.

'She told them she needed to take care of Kan. He was the guru,' Tibor said. Sharon cooked for Kan, massaged his feet and toes, and paid for a three-hour massage for him. At a train station, Sharon carried three suitcases while Kan walked ahead.

That's when Tibor became fearful. 'My daughter was going to die. I knew it,' Tibor said. 'I felt she was going to die.'

My daughter was going to die. I knew it. I felt she was going to die.

On August 6, 2011, Tibor received a terrifying call from the United States Embassy in Copenhagen, Denmark — Sharon had disappeared.

It turned out that Kan brought his dancers to the Christiana section of Copenhagen, a large commune well known for drugs and prostitution, where they squatted in a rat-infested abandoned building. By the time Tibor and his family arrived, Sharon had been found in a mental hospital.

'I believe he gave her some kind of drugs,' Tibor said. 'She was complaining about losing her memory. She doesn't remember the past.'

After five days, doctors released Sharon, but told Tibor that she needed immediate treatment.

Tibor brought Sharon home to Florida and made arrangements for her to enter a treatment facility on September 16, 2011. But before she could do that, Kan lured her away again, according to the lawsuit.

Kan 'disregarded Sharon's health and safety, and her parents' pleas to leave Sharon alone, and convinced Sharon to fly out of the country to be with him,' the lawsuit claimed.

'My wife and I — we never slept,' Tibor said. At night, they stood outside Sharon's door, listening. 'She's Skyping with the guy. He's telling her not to believe me, to come back to him.'

'He's the god,' Tibor said. 'She wrote, he's the god.'

'Under the guise of molding Sharon (pictured in Butoh makeup) into a Butoh artist,' Tibor's lawsuit stated, Kan 'intentionally and/or recklessly inflicted emotional pain and suffering on Sharon continuously from the day he met her until the day she died'

After graduating in 2009, Sharon continued to work for Kan (pictured), organizing Butoh performances and festivals around the world. Kan 'systematically stripped away Sharon's dignity, free will and self-respect,' the lawsuit claimed. He 'seduced Sharon, abused her physically and mentally, humiliated her, insulted her, and manipulated her'

In 2011, the Stern family were called by the US Embassy in Copenhagen who informed them Sharon had gone missing. She was found five days later in a psych ward. She had been squatting in a rat-infested abandoned building (pictured) with Kan and other dancers. Tibor photographed the conditions, with drugs openly displayed on a table in front of the building

Sharon sent Kan disturbing letter in months before her death Dear Kan, Sharoni is very sorry. She cannot helping KAN anymore. IF everything is secret, if everything is HIDDEN, I can't interpret your mystery. I AM MORE than imperfect. I am fat, ugly, stupid girl. I have nothing left but desire to connect with human race, escape time and subconscious. I guessing I must let go of attachment to KAN. KAN has wife and child. SHARONI has garbage, piles of garbage everywhere. I have only one very honest very sincere wish left. TO GO WITH KAN to some countryside and FAST, no food, no water. need no bed, no shower. NO TIME. TO become empty. want to shake this curse away. Still, forever sharoni loves kan. But this is all that is left. And if Kan can accept this imperfect sharoni, then maybe chance to survive. don't want to throw away this love. but if KAN cannot accept, sharoni is LOST forever. Advertisement

Kan sent Sharon an email on September 14, 2011, right before she was supposed to enter the hospital, which was submitted to the court. He wanted her to meet him in Chiang Mai, Thailand, and said he would be her 'personal psychotherapist.'

Sharon snuck out of her parents' home in the middle of the night, Tibor said, so she could fly to Thailand, using a ticket that Kan sent her.

'He found out she was sick when she arrived,' Tibor said. 'He wrote us emails saying why did you let her go? I don't want her.'

This happened multiple times. Tibor and his family got Sharon back, and then she left again to be with Kan. In San Francisco she had psychotic breakdowns. In Boulder, Colorado, she attempted suicide twice. In Tel Aviv she broke down crying.

By 2012, Sharon had divorced her husband and was living in her parents' home in Florida. But on January 4, 2012, Kan told her in an email that she was no longer his 'priority,' and if Sharon did not obey him, then the relationship was over, according to the lawsuit.

Heartbroken, Sharon sent Kan a disturbing email, which was submitted to the court as evidence. She wrote in the third person and called herself a 'fat, ugly, stupid girl.'

A few weeks later, according to the lawsuit, Sharon wrote an email to Kan, in which she said her brother would give her $250, but she needed more to follow Kan and help him. Sharon also wrote, 'I'm tired of life - no one helps me to help them. So now you please tell me how … please. need a way to DIE. really.'

In February 2012, Sharon reluctantly started seeing a psychologist, Dr. Eli Levy, whom she had spoken to when she was 19 or 20 years old.

'She was not the beautiful woman I had known,' Levy testified in a deposition. 'She was somewhat physically neglected. She was very sad, upset, angry. She felt in a way that her life was taking the wrong turn.'

Sharon had 14 counseling sessions with Dr. Levy, but could not let Kan go. She wanted to go a Butoh workshop to Brazil, hoping to see Kan.

Tibor, as her father, couldn't stop her; she was an adult and made her own decisions. But Sharon promised Dr. Levy that she would continue her counseling sessions via Skype.

Sharon flew to Brazil. Kan did not show up.

A few weeks after Sharon was taken back to Florida by her parents, she sent Kan an email asking for clarification about their relationship

Kan responded to some of her questions, telling her she needed to 'think with your weak head instead of ANGER', adding that his 'love has limitation, we can only share the creation on the stage'

Kan added: 'Your love is egoist not true love cause this big mess, you didn't accept my order back from SF to Boulder work for Butoh festival to meet Todd in India. Your priority is following your ego not me'

After Sharon returned to Florida, on April 23, 2012, she sent Kan a goodbye email, according to the lawsuit. She wrote, 'love you. that's all. thank you for all your important lessons … good life to you. wish i knew what else to do. u were my angel.'

In his reply, according to the lawsuit, Kan wrote, 'continue your research who you are in another world can be more deep than USA.'

On April 25, 2012, Sharon Stern, at age 32, committed suicide.

A year later, on April 30, 2013, Tibor Stern, heartbroken, filed the wrongful death lawsuit in Broward County, Florida. It said, 'Stern was reduced to a mere pawn in the hands of Kan who mentally and physically abused her, manipulated her, stripped her of even a modicum of free will, and utilized Stern as his mere instrumentality and his sexual and physical slave to the extent that Stern's entire existence became committed to gratify Kan's every wish and desire.'

'Kan deliberately and knowingly isolated Stern from her husband, causing Stern to divorce him and from her loving parents and brother, causing her to become estranged from her family,' the lawsuit said.

Kan, traveling the world, avoided service of the lawsuit for a year. Tibor's attorneys finally hired a top international investigation company, which located Kan and served him in Thailand.

Then Kan argued that, because he was a citizen of Japan and had never been to Florida, he could not be sued in Florida courts. But the judge ruled that Kan's email and Skype communications with Sharon, while she was in Florida, made him subject to the state's laws. Kan appealed the decision, and it took almost four years for the issue to be settled — that Kan could be sued in Florida.

In the meantime, Tibor Stern hoped to help other families who were trying to save loved ones from controlling individuals and groups. He founded Families Against Cult Teachings (FACT), a nonprofit dedicated to raising awareness about destructive, high-control, high-demand groups, and to provide victim services.

FACT has shut down 10 cults and provided information to law enforcement that lead to the indictments of five cult leaders, Tibor said. But that doesn't mean the cult leaders quit.

'They get indicted, but they will continue their activities,' Tibor said. 'It's a cancer. They go somewhere else and reopen. They reinvent themselves.'

After Sharon returned to Florida, on April 23, 2012, she sent Kan a goodbye email (pictured), according to the lawsuit. She wrote, 'love you. that's all. thank you for all your important lessons … good life to you. wish i knew what else to do. u were my angel'

In his reply (pictured), according to the lawsuit, Kan wrote, 'continue your research who you are in another world can be more deep than USA.' On April 25, 2012, Sharon Stern, at age 32, committed suicide

In February 2012, Sharon reluctantly started seeing a psychologist, Dr. Eli Levy, whom she had spoken to when she was 19 or 20 years old. 'She was not the beautiful woman I had known,' Levy testified in a deposition. 'She was somewhat physically neglected. She was very sad, upset, angry. She felt in a way that her life was taking the wrong turn'

So FACT is changing direction — instead of trying to shut cults down, the organization will focus on prevention.

'We came to the conclusion that it's like fighting cancer with a Band-aid, going after cult leaders,' Tibor said. 'My answer is education, bringing awareness and changing laws.'

While he was building FACT, Tibor's lawsuit dragged on. At one point Kan offered Tibor $1,000 to settle the case. Then Kan filed a counter-claim against Tibor, saying the wrongful death lawsuit was 'a misguided campaign' to damage his life and career.

In court documents, Kan said that Sharon showed up at his performances uninvited, and that he advised her to stay home with her family to rest and recover. He denied almost every allegation in Tibor's lawsuit and claimed they were unfounded.

But Ben Murphey, Tibor's attorney, sought the testimony of Dr. Eli Levy, Sharon's psychologist. Levy testified that while Kan had some positive effects on Sharon — he got her to believe in herself — mostly the effects were negative.

Reviewing Kan's emails, Levy said he believed Kan was a 'pathological narcissist.'

Kan was 'extremely controlling and manipulative, threatening to withdraw love and affection and mentoring, unless she's compliant and totally obedient to his dictates,' Levy testified.

'In my opinion,' Levy said, 'he breached a professional relationship between a mentor and teacher and a student. He took advantage of his position. I believe he abused her emotionally, physically, economically and sexually. I believe he misused his power and put her in a position of submissiveness, that she essentially had to surrender who she is and what she is, for the sake of getting his love, approval and recognition.'

Tibor (pictured with wife Hana), said he continued with the expensive six-year battle because he wanted justice. He did it so others will not endure the heartache of losing a loved one. 'I'm a very loving father and she was my best friend,' he said. 'I know who she was. I know what she became. The man needed to be found guilty'

A trial will take place in a few months and the court will decide how much money to award Tibor in damages. But Tibor doesn't care about the money. 'The guy doesn't have five dollars,'

'Reading through their emails,' Levy continued, 'I think that he essentially wanted to strip her and make her emotionally naked, and totally disconnect her from anybody else in a very insidious, in my opinion, power driven, control driven effort on his part.'

Levy testified that he believed Kan lost interest in Sharon and began to look for other women. But Sharon, he said, 'had given up everybody, including her husband, including her family. She had alienated everybody who loved her. She would not listen to anybody. And ending up essentially feeling that all her sacrifices were in vain.'

Ben Murphey, Tibor's attorney, said Katsura Kan was notified about Levy's deposition and had a year to present admissible evidence that he was not the cause of Sharon's death, but he never did.

Murphey filed a motion for a summary judgment on Kan's liability for Sharon's death. Kan could have attended the hearing on March 18, 2019, by telephone, but he did not show up. The motion was granted, which meant Kan was held responsible for Sharon's death.

Afterwards, Kan filed a response with the court, protesting that he tried to call the court but there was no answer. Writing that he was in an unfair situation, Kan said, 'Japanese Pro-se Defendant without Attorney and no proper technical knowledge of the trial still seeking the Fairness and JUSTICE.'

A trial will take place in a few months and the court will decide how much money to award Tibor in damages. But Tibor doesn't care about the money. 'The guy doesn't have five dollars,' he said.

What kept Tibor going through this expensive, six-year battle was his desire for justice. He did it so others will not endure the heartache of losing a loved one.

'When this ordeal happened, I didn't sleep more than an hour a night,' Tibor said. 'I was thinking about the factory worker who couldn't afford this. Why am I doing this? For them. I did it for all the parents.'

'I'm a very loving father and she was my best friend,' he continued. 'I know who she was. I know what she became. The man needed to be found guilty.'

'I did it for my daughter, did it for my family, did it for society.'

Donna Andersen is author of Lovefraud.com.

For confidential support call the National Suicide Prevention Line on 1-800-273-8255