Computer documents detailing a murder fantasy were found at the Victorian home of two killers who strangled a man and set his body on fire.
Christopher Leigh Coulter, 20, was sentenced to 25 years in jail for killing Drysdale man Russell Hammond as part of a joint criminal enterprise with his friend Garreth Giles.
Mr Hammond, 50, knew Giles well and offered him cash and a place to stay when the 26-year-old was temporarily forced from his mother's home.
Victorian Supreme Court Justice Elizabeth Hollingworth said Mr Hammond invited his killers inside for a drink when they arrived unannounced on his doorstep on January 5, 2012.
The pair then bound and strangled Mr Hammond, before driving his body to an isolated location where they burned it.
Justice Hollingworth described the murder as a senseless crime.
"You willingly participated with another person in the completely unprovoked killing of a trusting person, who had invited you into his home and shown you nothing but hospitality," she told Coulter on Thursday.
Police later found documents on Giles' computer which revealed he had been fantasising about killing somebody.
Justice Hollingworth said the murder fantasy was strikingly similar to the way Mr Hammond was killed.
Giles has been found guilty of murdering Mr Hammond but he is yet to be sentenced.
A jury last September found Coulter, of Leopold, unfit to stand trial due to his cognitive impairments.
But at a special hearing later that month the jury determined he had committed the murder, arson and theft.
Justice Hollingworth on Thursday sentenced Coulter to 25 years in prison, after the Department of Human Services found no appropriate placement for him in its residential treatment centre.
She said a substantial improvement in his behaviour could see him reassessed and placed in a residential program.
Giles and Coulter lived together with Giles' mother and sister, who Coulter has a young son with.
