(CNN) -- The Boston-area man who planned to kidnap children, rape and eat them is awaiting sentencing Tuesday and is seeking a prison term of 18 years followed by lifetime supervised release, according to court documents. Geoffrey Portway, 40, who pleaded guilty in May to distribution and possession of child pornography and solicitation to commit a crime of violence, submitted a document through his attorney to Massachusetts District Court on Friday, providing information to be used in imposing a sentence "sufficient but not greater than necessary," the court document says. The document includes background on the case, cites similar cases, and reasons for why Portway agrees to a term of 18 years, with a maximum of 21 years and 10 months. Such reasons included the contention that he "never engaged in inappropriate sexual conduct with a minor," that Portway will be required to register as a sex offender upon his release, limiting his future employment options, and there was "no evidence that (Portway) ever acted out any of his fantasies."
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Geoffrey Portway pleaded guilty in May to child porn and solicitation to commit violence
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Prosecutors say he planned to kidnap, rape and eat children
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His defense lawyer says Portway "lived in a fantasy world" and did not harm children
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Portway is scheduled to be sentenced Tuesday
But he added, "There's no evidence at all of @placeholder being involved with any child or harming any child."