Caution: This story contains material that may be disturbing to readers

Disturbing and gruesome details of the abduction and brutal murder of an 18-year-old girl were revealed in a Victoria, B.C. courtroom Monday as prosecutors argued that the two teenaged killers should be sentenced as adults.

The boys, who were 16 and 18 at the time of the murder, pleaded guilty last year to killing Kimberly Proctor, burning her body before dumping it on a rural trail near Colwood. The pair was charged with first-degree murder, forcible confinement, sexual assault and indignity to human remains in her death.

Text messages between the co-accused revealed that they had carefully planned the abduction and murder of Proctor.

Both boys had also been involved in joint rape fantasies for at least a year before the murder, according to a psychiatric report presented in the courtroom.

On March 18, after declining the boys' advances, Proctor was lured to a home of one of the boys where her hands and ankles were duct taped. They stuffed a sock in her mouth and sexually assaulted her for hours.

A knife was used to mutilate her body and she eventually died. An autopsy revealed she couldn't breathe because of the tape over her mouth.

Kimberly's parents and relatives sat in the front row of the courtroom as they heard that the boys both had sex with her after she was dead.

Her mother and father cried when they heard how Kimberly begged not to be hurt, and told her killers that she was sorry.

Crown prosecutors also revealed how the boys discussed using a funnel to pour Drano – a chemical drain cleaner – into Proctor's body.

Her body was placed in a freezer in the garage. The next day the teens carried her body in a duffel bag on a public bus to the Galloping Goose Trail, where they lit her on fire.

The teen's charred body was found near a bridge on the trail.

In online chats, the boys admitted to a friend that they had picked Proctor because she was an easy target.

The father of one of the teens is in jail for the brutal murder of a teen girl under similar circumstances.

Because the son is a young offender, neither he nor his father can be named, but the two killings were strikingly similar. Both girls were lured, beaten, bound, sexually assaulted, choked and killed.

In court last year, the boy said he had dreamed about killing someone since he was young, but offered no other reason for the murder.

Neither boys looked at the audience during Monday's proceedings – both stared straight ahead and only looked at the judge.

Punishment

The two-week sentencing hearing will determine if the young men will be sentenced as youth or adults.

A youth sentence for the teens would mean a minimum jail term of 10 years without parole. This jumps to life with 25 years without parole as an adult.

Crown prosecutor Peter Juk told the court that imposing adult sentences is the only way the pair would be held properly accountable for Proctor's brutal slaying.

In court, Crown lawyers played taped conversations between the boys as they were being taken to their first court appearance just three days after their arrest – and after two full days of police interrogation.

Juk said the casual banter between them proved they were "hardly affected" by the crime and "held their own."

Juk also contends the boys each changed their stories as the court date approached – accusing the other of the most horrific and disturbing acts.

A 40-person team from Vancouver Island RCMP clocked more than 20,000 hours during its investigation into Proctor's death, and conducted more than 250 formal interviews.

The details of Proctor's murder were so repulsive and appalling – some officers who worked the case have gone into counselling.