Mohamed Naddaf pleaded guilty to the criminally negligent manslaughter of Ashlee Brown, 25, who died in their "unkempt and dirty" Craigieburn home in November 2016.

Justice John Champion, in sentencing Naddaf in the Supreme Court of Victoria on Friday, said Ms Brown was found in the passenger seat of the couple's car after having been subjected to a "deliberate and frenzied assault" and tied up with clothesline wire.

Bloodstains were found throughout the garage and car, and Ms Brown had cuts and bruises across her body, which worsened over subsequent days.

Naddaf, 37 at the time, helped Ms Brown to the bathroom, laying her on a flannelette sheet on the floor, and feeding her water through a syringe for five days.

He finally called triple zero on November 6 after Ms Brown died from complications arising from her numerous injuries, and internal and external bleeding.

An autopsy confirmed Ms Brown suffered multiple blunt and sharp force trauma injuries to her head, buttocks, torso, arms and legs including stab wounds to her thighs.

By the time ambulance officers arrived, Ms Brown was "cold to the touch and stiff", and had been dead for some time.

Justice Champion said he did not accept Naddaf's claim that Ms Brown begged him not to call for help.

However, he said Naddaf's motivation was unclear.

"The Crown is not in a position to prove who inflicted the injuries upon Ms Brown," Justice Champion said.

"It is not possible to say exactly when Ms Brown died but ... she suffered to a considerable degree."

He described Naddaf's attempts at caring for her as "feeble and derisory" and "deserving of condemnation".

"She lay on the floor of the bathroom for four to five days where you allowed her deterioration," he said.

"All that was required was a phone call.

"Her death was slow, avoidable and miserable."

Right-wing activist group, the Australian Liberty Alliance, staged a protest outside court on Friday, chanting "justice for Ashlee".

Ms Brown's mother Siobhan told reporters after the sentencing she believed Naddaf should have instead faced a murder trial for the death of her daughter, who had converted to Islam.

"I am here today to raise awareness to the horrific, torturous death that Ashlee endured," she said outside court.

"My daughter's injuries and circumstances surrounding her death had all the hallmarks of an Islamic honour killing."

She described her daughter as a "ray of sunshine" who "loved life".

Naddaf was sentenced to 11 years' imprisonment and must serve at least eight years before being eligible for parole.

He has already served 621 days in pre-sentence detention.

Australian Associated Press