Shea Peter Heeley, 19, was jailed for life, to serve a minimum of 24-and-a-half-years, for the murder of 'lovely and lively' Leonne Weeks, 16, during a hearing held at Sheffield Crown Court this morning.
As Heeley was taken out of court to begin his life sentence, a member of the of packed-full public gallery shouted: 'Do us all a favour and hang yourself'.
Heeley was charged with Leonne's murder on January 20 last year, and the court heard how during his time on remand, Heeley said he had always known that he would kill someone, and later told staff in a secure mental hospital: 'I like that I have done it, I just do. I like killing'.
Heeley, who looked at the floor throughout the 80 minute hearing, had known Leonne for around 18-months, and had been seen at a house party with her just two days before her tragic death on January 15 last year, the court heard.
Judge Paul Watson QC told Heeley, dressed in a grey and black Nike sweatshirt and grey jogging bottoms: "You had, for reasons that will never be known, identified her as your victim.
"You had nurtured a friendship with her and had communicated with her repeatedly by text and social media. You then lured her to the place of her death - an intentionally isolated location - with the clear intention that you would kill her."
Heeley stabbed the beloved schoolgirl 28 times 'with substantial force' to her face, hands, forearms and body, before dragging her body a short distance away and hiding it under a discarded sofa, just off Lordens Hill, Dinnington.
Tim Roberts QC, prosecuting, told the court how in the hours following Leonne's death, Heeley contacted various friends and told them he had been attacked, which he used as an explanation for the cuts to his hands and the mud and rips to his tracksuit bottoms.
He said: "Even returning to the area of the crime with others who were unaware of what had just happened there, continuing a false story and constructing a false alibi."
Leonne's body was discovered at around 10.30am the following day.
Not only did Heeley return to the scene of the crime in the hours following her death, but he was among the crowd of people who gathered in the area after her body had been found.
Judge Watson added: "Others report you laughing when her death was being talked about, and it is quite clear that what you had done did not concern you in the slightest."
Heeley was assessed by psychiatrists and psychologists who said they did not believe he was suffering from any mental illness, but said he demonstrated symptoms of an 'emerging personality disorder'.
The court was told how Heeley had researched murders, serial killers and had Googled the search term 'how to get away with murder' online in the months leading to Leonne's death.
He is also said to have got a 'rush' from inflicting pain on animals, and said murdering a human was a 'milestone within his life' that he wanted to reach.
Heeley, of Doe Quarry Lane, Dinnington, pleaded guilty to her murder last month.
Defending, Alan Kent QC, said in mitigation that the fact Heeley had just turned 18 when he committed the murder and his personality disorder should be taken into consideration when imposing the sentence.
Judge Watson said: "In short this was a pre-planned, brutal and pitiless killing of an innocent young girl, who had her whole life in front of her. As a result of what you did, Leonne lost her life and her family lost a daughter, a granddaughter and sister. They will have to live with that agonising loss and the living nightmare of your evil crime for the rest of their lives. It is clear from all that I have read, that she was a lovely, lively, funny and caring young girl whose absence will leave a permanent hole in the hearts of the many who knew and loved her."