Elliot Turner, 20, was sentenced to life in prison with a 16-year non-parole period for strangling Ms Longley, 17, in Bournemouth, England, in 2011.
Emily's body was found in Turner's parents' Bournemouth home on May 7.
Turner is appealing against his conviction and sentence.
According to the Daily Star, Turner had pinned photos of Ms Longley on the wall of his cell at HMP Swaleside in Kent.
He also reportedly spoke about the day he would be released and return to his life of "champagne, Bentleys and birds".
An unnamed source told the paper that Turner, the son of a millionaire jeweller, had bragged to fellow inmates about fan mail he had received from women. He was attacked by some inmates shortly afterwards.
Turner had since been moved to another wing of the prison, the paper reported.
Turner's parents Leigh, 54, and Anita, 51, were jailed for 27 months in July for perverting the course of justice, after they destroyed a confession letter from their son and took evidence from the murder scene.
