A man who confessed to “numerous lies” while concealing his roommate’s corpse in a toolbox for multiple months has revealed to a jury that he was also untruthful when he admitted to her murder.

Yang Zhao, aged 30, concluded his third and final day of testimony in his defense on Friday during his murder trial in Queensland’s Supreme Court.

Zhao allegedly killed Qiong Yan, 29, by hitting her on the head with a metal bottle and then strangling her, as stated by crown prosecutor Chris Cook to the jury.

The jury heard Zhao claim his detailed accounts of killing Yan in a violent and bloody manner, given to police after his arrest in July 2021, were based on thoughts he had while intoxicated that he combined with “movies and TV dramas”.

“The only thing the jury should believe, that you have said, is that you murdered Qiong Yan?” Cook said.

“No,” Zhao said, with the aid of a Mandarin interpreter.

Cook said this version of events was based on Zhao’s three statements to police, given over three days, that all recorded him admitting to killing Yan.

Zhao pleaded not guilty to murdering Yan in September 2020 at their inner-Brisbane apartment.

However, he pleaded guilty at the start of the trial to interfering with Yan’s corpse by placing her in the tool box and leaving her on the apartment’s balcony for almost 10 months.

While on the stand, Zhao claimed Yan died accidentally after they had both spent up to four hours in the apartment inhaling nitrous oxide, which he referred to as “nangs” or “laughing gas”.

Zhao, a Chinese national living in Australia on a student visa, testified Yan passed out on the floor and stopped breathing while he was asleep on a nearby couch.

Yan was also a Chinese national and was the director of a migration agency.

The jury heard Zhao claim he hid her body because he was afraid of being charged with supplying drugs.

“At the time I didn’t know nangs were not illegal,” he said.

Zhao said he then unlocked Yan’s phone and impersonated her for months via text messages to her mother – Rongmei Yan – who was in China.

Rongmei Yan sat in the court and listened while Zhao admitted he stole $463,000 from her by requesting bank transfers while pretending to be her daughter.

Zhao also admitted drinking alcohol, using nitrous oxide and having sex while just metres from where Yan’s body was concealed.

He said he made false confessions in the belief he would get the death penalty, which he felt he deserved for hiding Yan’s body and stealing her money.

Zhao’s final minutes giving testimony on Friday were spent answering questions that had been repeatedly put to him in various ways during cross-examination.

“You attacked her that night. You intended to cause her serious harm. You killed her?” Cook said.

Justice Martin Burns is due to start summing up the evidence to the jury on Monday.