The college student identified as the Santa Barbara gunman wrote a lengthy autobiography detailing his increasingly violent views towards women and claimed he was a victim.
Elliot Rodger, who police identified as the man who killed six and wounded 13 in a furious rampage Friday, wrote a lengthy text called "My Twisted Life" that revealed his plans for the killing spree and his frustration with women and couples.
"All I ever wanted was to fit in and live a happy life amongst humanity, but I was cast out and rejected, forced to endure an existence of loneliness and insignificance, all because the females of the human species were incapable of seeing the value in me," he wrote.
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Read: Elliot Rodger's Trail of Carnage
In the text Rodger, 22, detailed his plans for revenge against women with his "Day of Retribution," where he planned to kill as many people as possible, including members of a sorority house, his brother and stepmother, and then take his own life.
"'How dare those girls give their love and sex to those other men and not me,' I constantly think when I see young couples," wrote Rodger. "There is nowhere in the world I can go anymore."
The perceived rejection apparently fueled Rodger's rage and the student wrote he felt that humanity had rejected him.
"The females of the human species have never wanted to mate with me, so how could I possibly consider myself part of humanity?" wrote Rodger. "Humanity has never accepted me among them, and now I know why. I am more than human. I am superior to them all. I am Elliot Rodger ... Magnificent, glorious, supreme, eminent ... Divine!"
"There is something very wrong with that. It is an injustice that cannot go unpunished," wrote Rodger of the perceived rejection.
In addition to detailing his frustrations with women, Rodger wrote that he was jealous of those happier and more successful than him, especially his younger brother. He planned to kill his brother even though they had "bonded" in the last year.
"I will not allow the boy to surpass me at everything, to live the life I've always wanted," wrote Rodger. "It's not fair that he has the chance to have a pleasurable life while I've been denied it. It will be a hard thing to do, because I had really bonded with my little brother in the last year, and he respected and looked up to me."
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Alan Schifman, the lawyer for Rodger's family, said the 22-year-old was being treated by several therapists and recently his parents and a social worker had become so alarmed by his behavior and his videos that they had reported him to police. Schifman said Rodger had always had trouble making friends and was diagnosed as a high-functioning patient with Asperger's syndrome as a child.
Schifman said he did not believe Rodger ever had a girlfriend and said the student had been a victim of bullying his whole life.
In one particularly chilling portion of the text, Rodgers revealed his room was stocked with weapons and evidence of his plans for the killing spree when police visited him in April.
"I had the striking and devastating fear that someone had somehow discovered what I was planning to do, and reported me for it," he wrote. "I would have been thrown in jail, denied of the chance to exact revenge on my enemies. I can't imagine a hell darker than that. Thankfully, that wasn't the case, but it was so close."
At the end of Rodger's text, he wrote he felt like a victim after experiencing so much loneliness and rejection growing up.
"I am the true victim in all of this. I am the good guy," wrote Rodger. "Humanity struck at me first by condemning me to experience so much suffering ... I wasn't the one who struck first ... But I will finish it by striking back. I will punish everyone."
Rodger was found dead of a self-inflicted gunshot wound after a shootout with police.
ABC News' Micah Grimes contributed to this report.
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