Since at least 1980, there have been hundreds of stories of same-sex couples in India getting married unofficially by religious rites, according to gender studies expert and author Ruth Vanita.
Some couples have even taken their own lives together as a form of union.
Ms Vanita traced the history of LGBT relationships in the country for her book Love's Rite: Same-Sex Marriages in Modern India, first published in 2005.
"They were [and are] young women from low-income groups — there were a few men too — who knew no English and were not in touch with any movement," Ms Vanita told the ABC.
"They simply said that they cannot part from each other and if they are separated they will give up their lives, which many of them did."
One of the government's main arguments in a landmark case being heard by India's Supreme Court on whether to legalise same-sex marriage is that the issue is an "urban elitist concept" that originates from Western culture.
But during the hearings, some of the couples' stories from Ms Vanita's book were presented to the court in submissions by the group of LGBT petitioners facing off against Prime Minister Narendra Modi's government.
"In the 1980s, there was no LGBT movement in India," Ms Vanita said.
"These unions continued through the 1990s when marriage equality did not exist anywhere in the world."
While LGBT rights have progressed in recent years, the community still faces stigma in the largely conservative country of 1.4 billion people.
And with marriage steeped in religious tradition, the topic of same-sex unions is particularly taboo.
Leaders from India's main religions — Hindu, Muslim, Jain, Sikh and Christian — have all separately written to the court voicing vigorous opposition to the issue, largely echoing the government's stance.
So even if LGBT couples gain the legal right to marriage, will those rights be culturally and socially accepted?
What religious groups are saying
In India, marriage is governed by a set of different laws tailored to the country's religious groups, and a secular law for interfaith couples called the Special Marriage Act.
All limit marriage to between men and women.
The Supreme Court is considering whether the act — which allows marriages between people of different castes and religions — can be adapted to include LGBT people.
However, the case is becoming increasingly complex with the government pressing the court on whether it has the right to hear a matter, saying any tweaks to the Marriage Act would also lead to changes to dozens of personal religious laws.
On Wednesday, the government proposed it could set up a committee to address concerns of same-sex couples without going into the issue of legalising their marriage.
The closely-watched hearings come five years after the court decriminalised homosexuality in the world's most populous country.
People from India's LGBT community told the ABC they were hopeful the court would again "come to their rescue" and grant them rights to be part of something that is part of their cultural identity.
But, under the Hindu nationalist government and the eyes of the "religious police" they said it was difficult to imagine a large progressive shift.
The Grand Mufti of India, Sheikh Abubakr Ahmad, has said that any form of marital relationship that is not between man and woman "is against natural law and impermissible".
Islamic religious body Jamiat-Ulama-I-Hind has argued that same-sex marriage is an attack on family values and is based on an "atheistic worldview".
Kapil Sibal, senior advocate for the organisation, told the court the "issue is of large ramifications" and would impact various laws such as inheritance, succession and adoption.
He also questioned whether India would embrace the court's decision.
"Supreme Court ready to hear. Is society ready to listen?" he tweeted.
In the past, when LGBT rights were in the headlines, the high-profile president of the Catholic Bishops' Conference of India, Oswald Gracias, said the Catholic Church was not opposed to homosexuality.
"We have never considered gay people criminals," he said in 2013, adding that "we express our full respect for homosexuals".
But when it comes to legalising same-sex marriage, Catholic officials are among the religious leaders that share the view that it is a Western issue imported to India, calling it "unnatural".
Hindu texts neither 'forbid or condone' same-sex marriage
About 79 per cent of India's population are Hindu.
The influential Hindu fundamentalist organisation Rashtriya Swayamsevak Sangh (RSS) has stood alongside the government with its long-held views opposing LGBT marriages.
But in January, RSS chief Mohan Bhagwat said in an interview that Indian civilisation has traditionally acknowledged the community and LGBT people are "part of the Indian society".
Although he did not specifically refer to marriage, he said they are "humans and have the right to live as others".
At the time, Mr Bhagwat's comments raised questions as to whether the group would push the prime minister's stance.
When hearings resumed this week, right-wing Hindu organisation Vishwa Hindu Parishad (VHP) held the first in a series of nationwide protests against the plea in the Supreme Court, saying it goes against the "ethics of Indian culture", according to local media reports.
When it comes to India and Hinduism, everything is "extremely complex", said Pandit Rami Sivan, a Hindu priest and spokesperson for the Australian Council of Hindu Clergy.
The caste system divides Hindus into four main categories, with Brahmins — who make up around 5 per cent of the population — being "very strict in their interpretations of those rules and regulations", Pandit Rami told the ABC.
For Brahmins, marriage is a sacrament, but Hindu marriages can also exist as a non-sacramental or "civil union", he said.
"Now when it comes to same-sex, there is nothing in the law — the Hindu law texts — which either forbid it or condone it."
Hindu same-sex weddings welcomed in Australia
The national body of Hindu priests and monks openly supported the "yes" campaign for Australia's same-sex marriage plebiscite in 2017.
"We, the Hindu Clergy, believe that all people regardless or race, religion, colour, gender or sexual orientation have the right to be treated equally under the law and that includes the marriage law," the group said in a statement.
"It will have no impact whatsoever on our ability to practise our religion or conduct our sacraments of marriage."
Since then, Pandit Rami has conducted four same-sex marriage ceremonies using adapted Hindu texts.
A recent wedding was with a Brahmin woman and everyone was "completely accepting".
"Everybody came up and said it was a beautiful ceremony," he said.
"There wasn't a single bit of reticence or anything, everybody was completely behind the girls getting married."
Pandit Rami believes that "the vast majority of Hindus are unconcerned" about same-sex marriages.
"And in actual fact, there is a concept in Hindu culture of the third gender," he said.
Ms Vanita said she had documented several same-sex couples who were married by Hindu priests in temples in India.
"All of these couples and their families are part of Indian society and culture," she said.
Will there be social 'havoc'?
The government has warned that the Supreme Court coming down in favour of same-sex marriage would cause "complete havoc" and be "against the cultural ethos of the country".
According to a Pew survey, acceptance of homosexuality in India increased by 22 percentage points to 37 per cent between 2013 and 2019.
There have also been more openly gay celebrities and some high-profile Bollywood films have dealt with gay issues.
However, the Bar Council of India (BCI) last month moved a resolution claiming that "more than 99.9 per cent of people of the country are opposed to the idea of same-sex marriage".
"[It] would be catastrophic to overhaul something as fundamental as the conception of marriage by any Law Court," the group said.
The BCI was slammed by LGBT activists and lawyers for being misleading, saying the figure was factually incorrect.
Dozens of LGBT collectives and more than 600 law students from across the country released a joint statement calling the resolution "ignorant, harmful, and antithetical".
Bijayani Mishra, an assistant professor of sociology at the University of Delhi, said it was unlikely 99 per cent of the population opposed same-sex marriage.
She said there had been clear changes in society with acceptance towards same-sex relationships, especially after homosexuality was decriminalised.
And even if people were brought up being taught marriage is a sacrament, it is inevitable different views will emerge.
"Because society is changing and social change is indispensable," Professor Bijayani told the ABC.
"You cannot pack society in a jar and say that society is not going to change.
"When society is not changing that means society is dead."
Currently, same-sex marriage is legal in 33 UN member states.
In Asia, Taiwan is the only place that currently recognises gay marriages, though pressure is building for reforms in Japan, Thailand and South Korea.
"In every one of the countries where there is marriage equality, exactly the same argument was made – it was against cultural values and would destroy the social fabric," Ms Vanita said.
"No such thing has happened."
In 2012, the government estimated the LGBT population in India was around 2.5 million.
But LGBT rights activists say the figure could be as high as 135 million, which is about 10 per cent of the population.
"Over time, as people get to know more visible couples and see that there is nothing to fear, many gradually change their minds," Ms Vanita said.
"This has already been happening in India for several decades."
Professor Bijayani said same-sex marriage rights will give LGBT people more security, but "society is not going to change overnight".
She said more needed to be done to support the socialisation process, including collecting more data, creating more scholarly work connected to the LGBT community and discussing issues with family.
"We are in the infancy stage ... there is hope that India will accept same-sex marriage but for that we have not yet done our homework properly," Professor Bijayani said.
"We need to keep talking about it, because we were not taught about same-sex or what LGBTQI+ is … There is a role of family, there is a role of academia and other people to be involved in the whole thing."
ABC/Wires
