A man accused of murdering his housemate by stabbing him 22 times after a drunken argument told police he made sure the last strike with the knife “went right through his heart”.

John Henry Waterfall, 69, denies murdering 56-year-old Fifita Mailau in the ramshackle cottage they both lived in in the Perth suburb of Mount Lawley in March last year.

On the eve of the anniversary of Mr Mailau’s death, Western Australia’s Supreme Court heard how the two men had both been drinking heavily when an argument erupted in the kitchen of the property.

Prosecutor Sean O’Sullivan told the jury that Mr Mailau had verbally abused Waterfall, calling him names including “poofter bastard”, and the older man snapped.

After retrieving a 24cm knife from his room, Waterfall stabbed the Tongan-born father nearly two dozen times, leaving the knife embedded in Mr Mailau’s chest.

The victim suffered fatal wounds to his chest, shoulders, neck, head and right arm.

Interviewed by police, Waterfall said: “I made sure the last one went right through his heart”.

In his opening address on Monday, defence lawyer Williams Harris said Waterfall, a rheumatic, had been terrified of Mailau whom he described as a “Jekyll and Hide” character after a drink.

“Everyone (in the house) was terrified of him … because when he drinks he goes off his head,” Mr Harris said.

He said Waterfall had told another housemate that Mr Mailau had him pinned up against a wall before he stabbed him.

The trial continues.