A man who stabbed a young woman to death repeatedly faked symptoms of psychosis while being assessed for a mental impairment defence.
Luay Sako, 39, told three psychiatrists there was a being called "Isha" who encouraged him to kill Celeste Manno in the early hours of November 16, 2020.
He claimed Isha told him he had become a criminal so he needed to act like one and end her.
But the psychiatrists, who were assessing if Sako was mentally unfit, each found he was faking the psychotic symptom.
"The description he gave was that she was concretely there - I wasn't convinced that was happening," Dr Rajan Darjee told the Victorian Supreme Court.
"He was exaggerating and he was trying to persuade me that he had a mental impairment defence."
Sako was found to be mentally fit, with the 39-year-old eventually pleading guilty to Ms Manno's murder in the Victorian Supreme Court.
The pair were briefly co-workers but he began harassing and stalking her after she turned him down romantically.
Over a 12-month period, he sent more than 140 messages to Ms Manno from a number of different Instagram accounts, with the communication becoming increasingly vulgar and degrading.
She went to police and obtained an intervention order against Sako but it didn't stop him contacting her.
On the night before her death, Ms Manno posted a photo of her boyfriend for the first time on Instagram.
A few hours later, Sako broke into her bedroom while she was sleeping and stabbed her 23 times.
Dr Darjee said it was clear he was jealous and the Instagram photo was the "straw that broke the camel's back".
"He was in a state of rage and desperation, and wanting everything to just go away - he wanted her and the situation to go away," the forensic psychiatrist said.
Dr Darjee diagnosed Sako with severe personality disorder, major depressive disorder and body dysmorphic disorder.
Those conditions were crucial factors to Sako's offending but they were not an explanation for it, the psychiatrist said.
"There was a significant impairment of judgment," he said.
Dr Darjee's evidence came after Ms Manno's family and friends shared their grief with the court.
Christopher Ridsdale, Ms Manno's boyfriend, said he was tormented by thoughts of the future they could have had together.
"This crime has changed my life, this crime has robbed us of a future," he told the court.
"I've lost my beautiful Celeste and nothing will ever change that."
Ms Manno's friend Sarah Pervaiz also confronted Sako, calling him selfish, apathetic and inhumane.
"I know there is nothing I could have done but it doesn't stop the immense feelings of regret," she said.
"No sentence will ever be enough but I would hate to see the system fail Celeste again."
Sako has admitted killing Ms Manno but argued he only caused two of the 23 stab wounds and the rest of her injuries came from broken glass.
The 39-year-old was originally representing himself in court but barrister Tim Marsh stepped forward to act for him on Tuesday afternoon, halfway through the plea.
The hearing before Justice Jane Dixon continues on Wednesday.
