Neighbours stepped in. One of them told Toafiga: "You could kill him, that's enough."
Toafiga responded: "I don't care". He also told neighbours that he wanted to kill Mr Otto.
Mr Otto died in hospital some days later. He had broken ribs and a broken arm caused by Toafiga's attack. He also suffered from pneumonia and Alzheimers.
Toafinga had originally been charged with Mr Otto's manslaughter but the Crown downgraded the charge after pathologists could not be sure beyond reasonable doubt that it was the attack that caused Mr Otto's death.
Toafiga's lawyer Steve Cullen said his client was sorry for what he had done and was not applying for bail.
Justice Timothy Brewer remanded Toafiga in custody until sentencing next month.