Software engineer Yang Guibiao, 28, moved in with his Beijing girlfriend a year ago, but the couple are getting married only next month.
Unlike a generation ago, when cohabitation was unheard of in conservative China, the couple are now part of a sizeable and growing majority of young Chinese born after 1980 who reject traditional social strictures.
Shanghai's Fudan University has just published a survey of 2,330 people - aged between 25 and 34 - from China's post-1980 generation. Among married respondents in Shanghai, 43 per cent had lived together before tying the knot.
"This is a revolutionary social change in China," said Chinese Academy of Social Science sociologist Li Yinhe.
She recalled that in a similar survey she had done in 1989, only 15 per cent admitted to cohabitation.
"Just two decades ago, remaining 'pure before marriage' was a social norm that everyone in China abided by," she said.
"Cohabitation no longer has the negative connotations it once had in China," said psychology researcher Chen Binbin, one of the academics behind the new study.
Couples now see cohabitation as a natural step after a relationship gets serious, with or without a marriage certificate.
But this wave of social liberalisation is still one with Chinese characteristics, say observers.
Some 95 per cent of those who had lived together before marriage said they already were engaged or had a clear plan to get married.
"We would not move in for the sake of it like couples do in the West," said Mr Yang. "I would only suggest it knowing that we were heading clearly towards marriage. We love each other and get along, so that's why we want to live together."
In fact, it was only after he had proposed to his girlfriend early this year, and a wedding date had been set, that the couple told their parents that they were living together.
"I wouldn't have dared to tell them before," he said.
Another unique aspect of cohabitation here is that the man is expected to pay for everything, unlike couples in the West who often move in together to save money.
"I would never pay the rent," said beautician Li Ru, 27, a Guangdong native.
She has been living with her 25-year-old hairdresser boyfriend for two years.
"The girl should never pay, it is not done that way here."
Ms Li said her mother has accepted the arrangement and the fact that the couple will marry only next year.
"Even if she did not accept it, it wouldn't have made a difference," she added.
It is also easier for young couples these days to move in together because they live and work in the city, far away from their parents back in their hometown.
In the face of this trend, there are those who wring their hands over the damage that cohabitation can do to marriages and especially to the woman, if the relationship falls apart.
Village officer Li Xuefei, 30, is dead set against cohabitation though she admits many of her friends are in such arrangements.
She and her businessman husband dated for seven years before they got married in 2010. She said they never thought of living together because it was inappropriate.
The couple have a two-year-old daughter.
"I hope I can pass on the right values to her," she said.
Professor Li, however, thinks that cohabitation will leave less and less of a mark.
"As the numbers (of couples living together) rise for each successive generation, even if a man wants a woman who is 'pure' in that sense, he might not be able to find one in China," she said.
This article was published on May 18 in The Straits Times.
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