She was charged for offences over three months, starting last December. Over a four-day period in late February alone, $16,000 was taken from Antunovich's account.
She said she was employed at a privately-run Ellerslie retirement home when she met Antunovich.
Since being charged, she had written a letter to the family and would pay the 99-year-old back, she said.
The aged-care facility said Devi was no longer employed there.
Devi said she'd never been in trouble with the law before. The Fijian, who is in New Zealand on a working visa, realised it was possible she could be deported. "I'm not sure about that. It's God's decision."
Devi will be sentenced on June 21.