Mai-Yia Vang was killed at a Butler Street property sometime on February 24 and February 25, 2018.

A Supreme Court jury earlier this year found Adam Margolis, 40, guilty of her murder after an eight-day trial.

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Margolis, who appeared in court on Monday for a plea hearing, indicated he would appeal his conviction and sentence.

The court heard Margolis and Ms Vang formed a relationship in January 2018 after they met through an online chat service.

Ms Vang then moved in with Margolis at his California Gully home on February 18 that year.

In the week leading up to Ms Vang's death, the court heard the couple had arguments about Ms Vang's apparent contact with an ex-partner.

After a "heated argument" late on February 24 or in the early hours of February 25, Margolis choked or strangled Ms Vang until she died.

The court heard in the proceeding 24 hours, Margolis used Ms Vang's phone purporting to be her.

He sent several messages in Ms Vang's sisters' group chat, telling them she was feeling sick and she needed to sleep.

Margolis then made plans to kill himself and wrote a 12-page email explaining why he killed Ms Vang.

He sent the email to three associates, one of whom received the email several hours later and contacted police.

Police arrived at Margolis' address in the early hours of February 27 to find Margolis lying on a mattress in his bedroom.

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The court heard he appeared to be having a drug overdose. Police asked him if there was anyone else in the property and he indicated to another bedroom.

Officers entered the room and found Ms Vang's body. She was lying face down with her torso on the bed and legs on the floor.

An autopsy report said there was male DNA on Ms Vang's neck and under her fingernails, which was likely to have come from Margolis.

Ms Vang's younger sister on Monday read a victim impact statement to the Supreme Court.

She said Ms Vang was a "kind-hearted and selfless" sister who played a "huge part" in her life.

The woman said it "felt like time had stopped" when she found out about her sister's death.

The woman said Ms Vang was killed in a "coward act" and that her sister was met with "egotism and cruelty" when she moved to Bendigo.

Ms Vang's father also broke down while reading a victim impact statement to the court.

He said his daughter was a "kind and generous" person who had been a passionate and dedicated student.

The man said his family was "deeply saddened" by his daughter's death.

"I can't come to the realisation that she is no longer with us," he said. "We are crippled by the ordeal. I apologise that as your father, I was unable to protect you."

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Crown prosecutor Mark Rochford QC told the court Ms Vang was a particularly vulnerable victim, given she was small in stature and had been living away from family and friends.

Mr Rochford also noted Margolis pretended to be Ms Vang in the hours after her death, and left his victim's body on the floor for hours after the murder.

Margolis, who represented himself in court, said he was not being "malicious" when he sent the messages to Ms Vang's sisters, rather he wanted to make sure his cats were looked after when he ended his own life.

Margolis told the court he "really, genuinely loved" Ms Vang but that she had told him to kill himself.

"It's not an excuse or motivation for murdering her," he said. "I say I did not murder her."

Margolis commended the prosecutor for his work "running the trial" and told the court he "believed he would have won" if he had different lawyers.

Margolis said "living around murderers" in prison had been "staggeringly difficult".

He told the judge he would be appealing his sentence because the jury was not told the "critical facts".

Mr Rochford said Margolis had not shown genuine remorse and his prospects of rehabilitation were "dim" because he did not have insight into his own behaviour and continued to "victim-blame".

Justice Christopher Beale reminded Margolis that it was not an appeal hearing and he needed to sentence Margolis because the jury had convicted him.

Margolis was remanded in custody. He is due to return to the Supreme Court next month for sentencing.

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