She was the prosecution's star witness during the trial 10 months later.

'I saw blood on my mother's chest'

That night, Chieko said, her mother had tucked in the three siblings in a first-floor bedroom, which was joined to a large bathroom. Her father was working overtime at the reclamation site at the time.

As she lay awake on bed, Chieko heard voices, then footsteps on the ground floor.

Then she heard screams coming from the bathroom.

"They were screams of pain from my mother."

She went to the bathroom and found her mother sitting on the floor.

"The man was pulling my mother's left hand and Obasan was pulling her right hand." Obasan is Japanese for auntie - a name her father had suggested she call Wong.

"I saw blood on my mother's chest. I cried and Obasan covered my mouth with her hand. I stopped crying and she released me."

Her mother sustained two fatal stab wounds - one gashed the neck and the other penetrated her abdomen.

Chieko went back to the room to wake her six-year-old brother, but he continued to sleep.

Then she saw Wong and Sim run down the stairs.

"My mother stood in the bathroom. She staggered a few paces and fell. I thought she was dead."

Her siblings were soon awake.

"All three of us stood outside the bathroom and cried. We were still crying there when Father got back."

When Mr Watanabe returned to the house, he was greeted by the wails of his children. He ran up and saw them standing outside the bathroom. Inside, he saw his wife, who was wearing a red dress, lying in a pool of blood.

Mr Watanabe asked Chieko what happened.

"My father asked me who did it. I replied: 'Obasan and a man whom I did not know'."

Sim was a stranger to Chieko, but she later picked him out from an identification parade as the man she saw struggling with her mother.

Sim's confession

Sim said that Wong first spoke to him about the plan to murder Mrs Watanabe on Jan 2, and offered him money.

On the night of Jan 6, they took a taxi to the victim's home. Wong had given Sim a tin half-filled with potty-cleaning liquid. In her bag, she had a pair of gloves and a knife.

When Mrs Watanabe asked what she wanted, Wong told her that she had brought a workman to repair a broken potty basin.

She let them in.

"I threw the liquid into the eyes of the woman," said Sim. "Wong stabbed her with a knife. The victim shouted - probably in pain - and covered her face with both palms while on the ground."

To keep Mrs Watanabe quiet, Sim covered her mouth but she bit his finger. That was also when Chieko saw him.

"After stabbing her (Mrs Watanabe) to death, Wong ran away. I chased her to the mouth of the road. We got a taxi..."

The next morning, Sim was arrested. Blood was found on a pair of trousers he had. It was found to be Type A, the same as that of the murdered woman.

During the trial, he also revealed his difficult relationship with Wong, with whom he had two sons. A year after their marriage, he said Wong assaulted his mother.

"This led my mother to dub her as 'empress daughter-in-law'",he said.

Sim never dared start a quarrel because "Wong would attempt to strike me".

"When I saw her in an aggressive mood, taking up a knife or stick, I would run for safety."

The one occasion when he was hit with a breadknife left a scar.

Their youngest son was less than two years old when Wong left him in 1963, before becoming a bar waitress. He said she would strut with her boyfriends in front of him.

"I advised her to refrain from such an action. I was hoping she would return to me."

'He killed her'

Wong put the blame for the death of Mrs Watanabe on her "greedy" husband.

After spending the morning and evening drinking, she said she went to the victim's home "just to slap her". It was not only because of what Mrs Watanabe had said about her, but also to give the woman another reason to complain to her husband. Wong said she wanted Mr Watanabe to end the affair.

She brought Sim along as protection, even though she hated him, because Mr Watanabe had told her most Japanese knew judo. She was afraid that this was true of Mrs Watanabe.

At the doorway of the children's bedroom, she slapped Mrs Watanabe. They were fighting in the bathroom when she claimed Sim threw the liquid at them.

"I asked Sim to run away but he refused."

She decided to leave and tripped down the stairs. It was only when she was outside that Sim joined her.

"If I had not been drinking that day, this incident would never have arisen," she said, insisting there was no way she could have stabbed Mrs Watanabe.

"I am only a woman and have also not the strength to stab her especially when she was biting my left finger and grabbing and scratching my right hand."

Wong also denied being a member of an all-woman secret society known as the Red Butterfly Gang - an accusation which had been made by Sim.

Testifying for the defence, psychiatrist Dr Wong Yip Chong said Wong had seemed prepared to be the "subordinate woman" in Mr Watanabe's life.

He said she tried to be nice to Mrs Watanabe, even sending her presents through Mr Watanabe.\

But the wife "was not only downright ungrateful, but also insulting and humiliating to Wong", said the doctor.

This affected Wong, whom he said could have been suffering from a viral brain infection. She could have caught the Japanese encephalitis virus from Mr Watanabe, he added.

Worried husband

In court, Mr Watanabe described his lover as a "lady with a forceful temperament" and a "strong drinker who could hold her drinks".

While his wife disapproved of the affair, he said he could not end it suddenly.

"Wong had hinted to me on several occasions in angry tones that if I were to sever my ties with her, something drastic would befall me or any member of my family."

He admitted he was thinking of leaving her, and that she suspected this.

On the day of the murder, Mr Watanabe had dinner with Wong at their Everitt Road place at 7.30pm.

She asked him if he would be staying the night. He spurned her, saying he would be going home to his family.

He also said that after his wife's death, Wong, who had a flair for hysterics, saw him at the Criminal Investigation Department.

She knelt on the floor.

"She told me in English: 'I am sorry. Give me see your wife, can or not? That night I drunk. I love you true. You told me everything finished."

The verdict

After a trial lasting 26 days, Wong and Sim were convicted of murder and sentenced to death on Dec 7, 1970.

Wong became the first woman to receive the capital punishment from a Singapore court. Both showed no emotion.

After unsuccessful appeals - including one to President Benjamin Sheares - both went to the gallows at Changi Prison on Jul 27, 1973.

They were buried side by side.

Who was Mimi Wong?

Police found that she was the daughter of her father's second wife. She was just 11 months old when he died.

At 14, she was already working as a packer.

She was 17 when she met Sim Woh Kum at a picnic. In 1958, when she was 19, they married.

A year later she gave birth to a son. In 1962, another son came.

Money was tight, and she had to do odd jobs in restaurants. Her husband lost his job after he was caught gambling.

She left him and became a dance hostess.

In 1966, she met Mr Hiroshi Watanabe. She claimed she got pregnant and he refused to give her money for an abortion, saying he had none. After she went to Penang for an abortion, Mr Watanabe continued the relationship.

During their affair, she met a Hong Kong businessman and fell head over heels for him. He took her to Hong Kong. Even so, she still continued to send Mr Watanabe love letters. When she got pregnant, her Hong Kong lover kicked her out.

She returned to Singapore and gave birth to a daughter. Mr Watanabe continued to visit her.

She worked as a social escort for a time to make ends meet.

In the middle of 1969, she became Mr Watanabe's mistress. He gave her $200 a month, and rented a room at Alexandra Road for her. A few months later, they moved to Everitt Road. She even hired a servant.

Now 25, Loh is still healing from the wounds of her military past. And she finds herself grappling with questions about her future, like whether any company will ever employ her, or whether she will ever be able to have a biological child.

And so, though speaking out carries risk, silence for Loh is not an option.

"People are not getting housing, people are not getting jobs ... that's basically what we're fighting for," she says. "We just want to help people survive another day, another month, another year."

At the heart of the debate over gender recognition laws is the importance of identity.

The legal documents that define our identity are crucial to navigating life and the world, from getting a bank loan to crossing a border. In much of the world, changing gender markers on identification documents remains impossible. Other countries allow such changes, but often with draconian prerequisites including sterilization, psychiatric interventions, and --- for any married person --- mandatory divorce.

"There's a lot of requirements in most of these laws imposed on trans people which are all violating the basic human rights --- the right to privacy, the right to bodily integrity, the right to non-discrimination, the right to identity," says Julia Ehrt, executive director of the International Lesbian, Gay, Bisexual, Trans and Intersex Association, or ILGA World.

Surgery makes some transgender people feel more comfortable in their bodies, but others consider it medically unnecessary, invasive and painful or prohibitively expensive. Some people simply cannot have it for medical reasons.

Gender-confirmation surgery can involve a variety of procedures that alter a person's sexual characteristics, some of which lead to permanent sterility. While the law in some countries explicitly spells out that sterilization must be an outcome for legal gender recognition, in most cases the ultimate intentions behind these policies are unclear and likely varied. But whether rendering transgender people sterile is the goal of these mandates, it's generally the result.

In the U.S., 13 states and territories have a surgical requirement to update gender markers on birth certificates, and four require it for updating driver's licenses, according to Olivia Hunt, policy director for the National Center for Transgender Equality. The states do not clarify what procedures they will accept.

Even after surgery, the process of obtaining a legal gender change can be convoluted and humiliating. In Australia, two states require two separate examinations of post-surgery genitalia by doctors, who must sign statutory declarations confirming "a surgical procedure involving the alteration of a person's reproductive organs." Any false statement by the doctor, the New South Wales state form warns, could result in two years' imprisonment.

"We don't even force s*x offenders to be sterilized in this country, but you're forcing transgender people just to get a birth certificate? Come on," says Kirsti Miller, a New South Wales woman who underwent gender-confirmation surgery in 2006, and was forced to divorce her childhood sweetheart. New South Wales removed the divorce mandate in 2018.

In Singapore, the surgery requirement has affected even children, says Coen Teo, executive director of TransBefrienders, a non-profit supporting transgender youth.

Singaporeans under 21 must get parental consent to undergo gender-confirmation surgery, a landmine for transgender children reluctant to tell their conservative families about their transition. But if they don't, they are required at many schools to use bathrooms and wear uniforms that match the gender marker on their national identity card, causing anguish.

"They don't feel themselves in school, so they can't concentrate in school, so a lot of them don't do well. And I'm speaking from experience," says Teo, a transgender man.

Most gender-confirmation procedures are not offered in Singapore, forcing several teens at TransBefrienders to travel overseas and spend possibly tens of thousands of dollars.

"They want to get back in school, they want to get back their life," Teo says. "It's a huge hurdle for them."

In a statement to The Associated Press, the Ministry of Home Affairs said the information on Singaporeans' national identity cards reflects a person's "s*x," which the government determines based on the person's "biological and physical attributes." To change that marker requires "proof of surgery, and the complete alteration of one's physical reproductive attributes," the ministry said.

"This allows the government to implement policies and laws based on s*x in a consistent manner," the ministry said.

Human rights watchdogs have spent years demanding an end to policies like these. In a 2013 report, the United Nations Special Rapporteur on Torture urged governments to outlaw forced or coerced sterilization in all circumstances. The following year, seven U.N. agencies, including the World Health Organization, said gender recognition policies requiring sterilization "run counter to respect for bodily integrity, self-determination and human dignity."

Many countries have been slow to respond. In 2019, Japan's Supreme Court upheld as constitutional the country's gender recognition law that requires surgical sterilization.

Some governments, however, have made changes. In 2012, Argentina became the first country to grant legal gender recognition based entirely on self-determination. In 2018, Sweden became the first country to financially compensate transgender people who were sterilized under its old policy.

Germany is considering similar compensation. Around 10,000 transgender Germans were sterilized under the country's former policy, according to advocacy group Bundesverband Trans(asterisk).

Cathrin Ramelow, a 58-year-old German transgender woman, is fighting for compensation and an apology from the government. In 2000, she underwent surgical sterilization, welcoming the chance to end her double life. But afterwards, she says, she agonized over what she had lost.

"You know there's something wrong with you and you can't have children anymore," she says. "I cried some days."

Years later, Loh would make the opposite choice. But she found that it, too, came with a steep cost.

Tucked against the wall of a spare room in Loh's apartment is the camouflage backpack she carried during her two years of enforced military service. One recent afternoon, she plunges a slender arm inside it and pulls out her old helmet, staring at it briefly before shoving it away.

They are artifacts of a time she likens to torture. She remains vanishingly thin from the eating disorder she developed during her service, an attempt to counter the masculinization of her body from the intense physical drills.

Loh is a poet with a wide grin, brainy and sensitive, eager to chat about philosophy, politics, art and music. But when she talks about her army days, her easy laugh turns nervous and her face goes dark.

She was raised as a boy by a protective mother and a conservative, stern father she grew to fear. Though he socialized Loh to be masculine, she knew early on that her body did not match who she was. Her first realization --- or "flash point" --- that something was off came one night at age 8, when she caught her distorted reflection in a window and suddenly imagined herself with long hair.

More flashpoints would follow until at 17, she read an article about transgender people coming out late in life. That was, she says, the moment her "egg cracked": How much longer will you wait, she asked herself, before you live the life you want?

She would wait one more year, until after her father had left the family. Her mother, Stella Wong, would embrace Buddhism, and ultimately Loh's identity.

"Everything is impermanent, whether you are male or female," says Wong, whose normally cheerful manner morphs into rage when strangers stare at her daughter. "In Buddhism, gender is nothing."

Yet by the time Loh began transitioning, she had been conscripted under Singapore's National Service requirement.

The Ministry of Defense's public position on transgender people --- reiterated in a statement to the AP --- is simply: "Those who are legally declared female will not be required to serve."

There are backdoor ways to sometimes get an exemption, but they are unofficial and often unknown, as with Loh. And she did not want to undergo sterilizing surgery because her conservative upbringing left her wanting her own biological children --- or at least the potential for them.

"Does the government not want trans people to have children of their own?" she asks.

And so, riddled with dread, she started her service, steeling herself as the silky black hair she had begun growing out was summarily shaved off.

The other soldiers made sexual comments and asked what color underwear she was wearing. One man repeatedly asked for s*x in messages that left her so frightened, he began haunting her nightmares.

She despised combat training, having to roll around in the jungle with the men. She cried afterwards in her mother's arms. Panic attacks set in. She became suicidal.

Poetry was a lifeline. In between exercises, she lay in her bunk, typing poems into her phone. After her shifts, she put on makeup and a wig and went to open mic nights around the city that drew members of the LGBTQ community.

One poem she wrote then, "Moonface," detailed her exhaustion over her warring identities, "that whiplash whenever you take off the wig."

"I just felt like the faces of the moon. Sometimes you're showing half your face," she says.

She survived her service and entered university, where she fully socially transitioned. But her legal status as male continued to cause problems, forcing her to live, uncomfortably, on the male corridor of her dormitory. She was arrested for participating in a protest for transgender rights without a permit outside the Ministry of Education building, and given a year's probation.

Meanwhile, Loh found herself fretting about her future in ways most early-20-somethings don't have to. She wanted to start hormone replacement therapy, but worried it would permanently affect her fertility. And she could not freeze her sperm for non-medical reasons because "social freezing" is not allowed in Singapore.

Loh researched fertility clinics overseas, but became discouraged by the cost and the complexities of accessing her gametes, or reproductive cells, from Singapore. She began to rage at the limitations placed upon her life.

"I have no avenue to fall back on," Loh says. "I have to go to another country to possibly pay more to preserve my gametes. Why do I have to go through all that? Why do I have to risk my own body?"

Loh had to weigh more than the risk to her fertility. She had to weigh the risk a mismatched ID card could pose to her life.

In 2019, Loh and her family travelled to neighboring Malaysia for a day of shopping. Loh handed the Malaysian immigration officer her passport, which lists her gender as male.

The officer stared at Loh, and when she spoke, her voice was steely. "You should go cut your hair," she snapped.

The words sent a chill through Loh. She knew that in Malaysia, simply being transgender is considered a crime. She had read stories about transgender people there being mobbed and killed.

She hurried across the border. Now, she makes sure to sweep her long hair back at checkpoints.

"I'm terrified of traveling now partially because of that," she says. "I still think about it to this day."

Given the prevalence of violence against transgender people, mismatched IDs can present a grave danger while traveling, says Ehrt of ILGA World.

"When you're in a position of vulnerability such as you are at a checkpoint, or you need to cross a border, then of course it's aggravated when your ID doesn't match," Ehrt says. "If a trans person of color has a nonmatching ID card and wants to cross a border, that is a catastrophe."

A 2015 survey of nearly 28,000 transgender people in the U.S. found that almost a third of those who presented a mismatched ID had endured negative experiences, including harassment and assault, according to the National Center for Transgender Equality, which conducted the study.

For a few, the fear of discrimination is so intense that they are reluctant to leave not only their country but even their house.

Jojo, a 32-year-old transgender woman, has spent years largely confined to her parents' Singapore home. She spoke on condition that her full name not be used to avoid harassment.

"The thought of being in situations where I need to present the identity card and having confrontations terrifies me," she said by e-mail.

She steps outside only occasionally for short walks, and survives on the support of her financially strapped parents. She has no current plans to undergo surgery, and thus no prospect of obtaining an identity card that matches how she looks. She hopes one day the surgery requirement will be replaced with something less invasive, such as requiring a person to live for two years in their preferred gender.

Loh doesn't see that happening any time soon.

"I feel like the earth will cook us alive faster than we can get legal gender recognition," Loh says. "It's an uphill battle and I'm already exhausted."

For those whose identities are denied by the state, the result can be financial ruin.

This is particularly true in Singapore, where government benefits are designed around heterosexual families, especially when it comes to finding a home. Eighty percent of Singaporeans live in government-subsidized housing. The catch: If you're under 35, you can only get that housing if you're married. And same-s*x marriage remains banned.

"The reality is that the gender marker in Singapore is something that gives you access to different things and different resources," says Loh. "Every single policy that benefits people is tied to getting a heterosexual arrangement."

At 25, Mick Yang wonders how much longer he will have to wait before he can afford to move out of his parents' home. As a transgender man who opted against sterilizing surgery, the state still considers him a woman. So he cannot get married and thus cannot access subsidized housing for at least another decade.

The policy also means his chances of having a biological child are slim, as only married women are allowed to use frozen eggs to conceive.

"I don't like the idea of not even having that option," says Yang. "As I get older and more of my peers move into that life stage, then I think it gets more aggravating and agonizing to feel that lack of freedom and rights."

Conversations with colleagues excited about their new subsidized apartments leave him feeling gutted.

"I've contributed just as much to this place and care as much and yet I cannot etch out a home for myself or any conceivable future family," he says.

Having a mismatched ID can also limit transgender people's employment prospects.

Although Teo of TransBefrienders passed the interview for an aviation training role, he was rejected after he produced his ID, which outed him as transgender. His would-be employers, he says, told him the conservative Ministry of Education might reject his application to be a trainer because his appearance clashes with his gender marker.

It all becomes a frustrating loop: Because finding work is difficult, transgender people tend to be less affluent, which means many can't afford unsubsidized housing, let alone the surgery for a legal gender change.

Among the many fears Loh has about her future, finding a job tops the list. "Will they reject me because I'm trans?" she wonders.

Loh's mother worries about how her daughter will navigate a future in which so many options have already been ripped away.

"But I have no choice," Wong says. "Because in Singapore, we abide by the rules. Me too."

Loh finds solace in the rare spots on the island that feel cocooned from the rules. One recent evening, that spot is a softly lit loft where poets have gathered for an open mic night.

Loh laughs and embraces her friends, sliding past a bar lined with more books than bottles of booze. The crowd is a mix of genders, races and sexual orientations.

Here, there is no judgement, no stares, no ID cards required. Loh revels in the freedom to be herself. "This is literally my space," she says.

She sifts through her phone, debating which poem to perform, ultimately selecting one about her hard-won identity as a woman.

Soon it's her turn at the microphone. The audience listens, rapt, snapping their fingers in support as she lays bare her pain and perseverance.

The applause washes over her. She smiles as she is seen, by her peers if not her government, for exactly who she is: A woman.