Jody Arias' 'voracious sexual appetite' and 'extreme obsession' led her to kill according to new book by TV news host HLN TV host Jane Velez-Mitchell writes that Travis Alexander had a full-blown addiction to sex with Jodi Arias Exposed: The Secret Life of Jodi Arias hits shelves August 20 A new book about convicted murderer Jodi Arias reveals the killer's nymphomania and victim Travis Alexander's inability to stay away from her helped lead to his grisly 2008 murder. HLN TV host Jane Velez-Mitchell's new book about Arias and the Mesa, Arizona murder of her on-again off-again lover Travis Alexander details the torrid affair that preceded the grisly 2008 crime. Exposed: The Secret Life of Jodi Arias hits shelves August 20 and goes far deeper into the sordid tale's sexual underpinnings than any reports have gone thus far. Deadly attraction: HLN TV host Jane Velez-Mitchell details the mutual sexual obsession between Jodi Arias and the man she murdered leading up to the crime in Exposed: The Secret Life of Jodi Arias The New York Post published an excerpt from the upcoming book. "Jodi elicited Travis" reckless forbidden passion," writes Velez-Mitchell of the practicing Mormon. Unfortunately for her, it was also what Travis loathed, as it came with more and more guilt each time. Velez-Mitchell says a close friend of Alexander's described Arias as a "sexual dynamo.' "We were driving one day," revealed Taylor Searle, "and [Travis] was talking about Jodi and was describing how she was a nymphomaniac. He was explaining that Jodi had gotten herself off eight times in one day. It might have been nine, or it might have been 13. Velez-Mitchell reveals a deeply unhealthy, sexually charged dynamic between Alexander and Arias that extended even after Alexander broke things off with his future murderer in 2007. Insatiable: Velez-Mitchell reveals that Travis Alexander, though a practicing Mormon, just couldn't stay away from Jodi's forbidden fruits Not long after the breakup, the two began having sex again. And according to the book, Alexander was desperately torn between following the dictates of his Mormon faith and those that came from inside himself. Desperate to stay near her obsession, Jodi offered to clean Travis's house for $12.50 an hour. And unable to stop himself from keeping her around, Travis gave Jodi the keys. Unfortunately, giving Jodi access to his house meant Travis was able to keep his addiction to his guilty pleasure full-blown. The pusher was right there serving him his drug on a silver platter," writes Velez-Mitchell. But as Travis began to date other women and distance himself from his fiery former lover, Jodi became progressively unhinged. Motive? As Arias awaits the sentencing portion of her trial, Exposed: The Secret Life of Jody Arias puts together the pieces of her sordid life that led to the murder of Travis Alexander "Whether it was because of his upbringing or Jodi's skills in the bedroom," writes the TV host, "Travis clearly had a difficult time deciding what he was going to do about Jodi." And Travis's forays into the "dark side" were hurting his chances of leading the normal Mormon life he so desired. "Already, she was having Mormon guilt about kissing Travis to the point where he had an erection," writes Velez-Mitchell about a Mormon girl Travis dated after She was so naïve about the situation inside his pants, she assumed it was something he could control, not an act of nature. She also thought it was somewhat her fault that she had not done enough to keep his thoughts clean. Addict: Velez-Mitchell writes that Alexander called Arias a 'sexual dynamo' and likens his desire for her to that of a junkie and his drugs--deadly but irresistible Jodi's behavior became progressively erratic - she began stalking Travis when he was with other women and hacking into his Facebook account. She would show up to his home naked and unannounced. Though she eventually moved back to her home town in California, the world would soon learn how quickly she returned to Travis's Arizona home. On June 4, Arias showed up in the early morning hours. She and Alexander had one long and final sexual encounter. That evening, Jodi would stab her former lover some 29 times, shoot him in the face, and slice him ear-to-ear. Their insatiable sexual affair had come to a bloody end.