Alyssa Bustamante, the killer of her neighbour girl,seek emotional appology from victim's family.

A teenager named Alyssa Bustamante who murdered a girl for living in her neighberood has been sentenced to lifetime imprisonment. But he called it "enjoyable" may have the opportunity to walk free one day. The 18 year-old teen expressed remorse for brutally killing her neighbor, Elizabeth Olten, in October 2009, in what prosecutors described as a thrill killing.

"I know words can never be enough and they can never adequately describe how horribly I feel for all of this," Bustamante said to Olten's mother and siblings, who sat silently. "If I could give my life to get her back I would. I'm sorry."

Bustamante stabbed the 9-year-old girl in the chest, strangled her, sliced her throat and left her in a shallow grave covered with leaves so she could find out what it felt like to kill.

"I just f***ing killed someone. I strangled them and slit their throat and stabbed them now they're dead. I don't know how to feel atm [at the moment]," Bustamante wrote in her diary. She later added: "It was ahmazing. As soon as you get over the 'ohmygawd I can't do this' feeling, it's pretty enjoyable. I'm kinda nervous and shaky though right now. Kay, I gotta go to church now...lol." Elizabeth's mother, Patty Preiss called Bustamante "an evil monster" and said that she "hated her" on the first day of the teen's sentencing hearing.

Prosecutor Mark Richardson had argued for life in prison, plus 71 years, accounting for the years Elizabeth lost. The defense cited Bustamante's depression and a suicide attempt as a reason for a reduced sentence.

On the teen's YouTube page, a video appears to show the suspect with her brothers purposefully shocking themselves on an electrified fence. She listed "killing people" as one of her hobbies under her profile.

Her Twitter messages around the time of the murder spoke of "addiction" and "terrors." One message said, "all I want in life is a reason for all this pain." "She committed the murder after deliberation, which means cool deliberation or cool reflection on the matter for any length of time," Cole County prosecutor Mark Richardson told the court Wednesday.