She often went to work covered in bruises.
In February, the waitress had an injury on her left ear that required stitches.
Ms Annie Ee Yu Lian, 27, was found dead in a flat on the third storey of Block 878, Woodlands Avenue 9, on Monday morning.
The Singapore Civil Defence Force said that its paramedics had found her body, with no visible fatal injuries, on a mattress in a bedroom.
A married couple who lived with Ms Ee in the flat were arrested in connection with the case. The police confirmed that it was murder yesterday evening.
The man, 36, and his wife, 31, are understood to be the owners of the flat.
Two neighbours, who declined to be named, told The New Paper yesterday that the couple moved in about five years ago. But they were not sure when Ms Ee started living there.
They said that while Ms Ee was not related to the couple, the two women addressed each other as "sisters".
One of them said that she worked as a waitress in Hot Tomato restaurant at the nearby Causeway Point shopping mall.
She said: "I think she was a tenant in the flat and the owners often kept to themselves. The few times I saw them, they seemed to be in a bad mood.
"I had seen the waitress in the restaurant a few times when I walked past it. We never spoke, but she seemed fine."
But a manager in Hot Tomato, who was interviewed by the two Chinese evening dailies, told a different story.
Lianhe Wanbao quoted the unnamed manager as saying that Ms Ee often turned up for work with bruises on her arms and face. Shin Min Daily News said that she would try to cover up the bruises with concealer, with her fringe or by wearing a cap.
The manager said: "When we asked her about her injuries, she would evade the question or said she had hurt herself accidentally or had fallen."
Ms Ee began working at the restaurant in November 2013, earning about $1,500 a month. Her former colleagues described her as a gentle person who sometimes joked with them.
The manager said she started showing up with bruises last October.
And she would freeze and appear frightened at the mention of her " big sister".
He said the "sister" would call the restaurant often to check on her.
"She had to knock off at 10pm sharp every day. Once, I kept her back because I was teaching her something. Her 'sister' called the restaurant and scolded me," he said.
The manager told Shin Min that the "sister" was upset with the amount Ms Ee got for Chinese New Year from the restaurant in February.
She called the restaurant to demand, unsuccessfully, that she get at least a month's salary as bonus. She then told Ms Ee to quit.
Ms Ee's bruises became worse. She took medical leave to treat an ear injury that had worsened and needed surgery, the manager said.
He said that a colleague was so shocked by her bruises in February that she took photos of them with her mobile phone. Ms Ee then confessed that her "sister" had beaten her.
She left Hot Tomato and got another job as a waitress in a Japanese restaurant in Causeway Point, earning about $1,400 a month.
The manager who interviewed her for the job told Shin Min that he found it odd that her "sister" was doing all the talking while Ms Ee kept silent.
Workers there said that she turned up for work last Wednesday with a red, swollen face and had difficulty walking.
They told her to go home and she left at about 7pm that day.
A neighbour told Shin Min that she had seen Ms Ee and the "sister" having a heated argument with the husband on Sunday afternoon.
Two other neighbours said they had heard two loud sounds coming from the flat that night.
This article was first published on Apr 15, 2015.
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