Her horrified flatmates placed her in the shower to put out the flames. One flatmate told the Nine Network of the horrific scene they came across.
"She was screaming, she was on fire... her clothes, carpet and her bed on fire... [she] was burning down her neck, chest and her fingers all the way up [her arm] was very severely burned," the flatmate, Phillipa Allanson, said.
"It just broke us, we couldn't even be in the house while she was getting treated by the ambulance," Allanson told 9 News.
Coles was rushed to Royal Brisbane and Women's Hospital in a serious condition for treatment of burns to her arms, chest and airway.
She had surgery overnight and is currently in a coma in the intensive care unit, but remains in a stable condition.
Police have called the attack "violent and brutal".
It's believed the couple may have only been together a short time.
His lawyer Corey Cullen told the magistrates court: "He's been assessed by mental health this morning and is suffering severely from schizophrenia."
Detective Acting Superintendent Mick O'Dowd said Coles' burns were of a "second degree nature".
"We understand they are known to each other, but how long that association between the two has existed we're unsure."
Supt O'Dowd said the thoughts of police were "with the victim".
