A man who described himself as the Devil raped a teenage girl and attacked three other women on the same night.
John Hinton’s five-hour rampage began when he grabbed two women in their 20s, pinning one to the ground before trying to rip her clothes off, a court heard.
He then followed a 17-year-old girl, put a hand over her mouth and sexually assaulted her.
Finally he punched a 15-year-old girl to the ground and raped her after threatening to slit her throat.
Jonathan Seely, prosecuting, said: "She fell unconscious and when she came round he told her to shut up or he would kill her and ordered her to come with him to the park.
"He threatened to slit her throat before he raped her. She believed if she tried to run away he would kill her. The attack lasted about 20 minutes."
After the horrific rape he asked his victim on a date, showed her a magic trick and bragged about attacking other women earlier that night.
In a diary written while held in prison Hinton wrote: "I still feel like killing and eating somebody. I'll catch the prey and tie her up."
Later he wrote: "I am the devil."
John Lloyd-Jones, representing Hinton, of Peterborough, Cambs., said his client had "extremely dark and disturbing fantasies".
Hinton, 23, who admitted rape, attempted rape, sexual assault and wounding, was jailed indefinitely at the city’s crown court.
He will have to serve a minimum of six years.
Judge Nic Madge told him: "There is a serious risk of danger to the public by further offences by you.
"You will be released only when it is no longer necessary for you to be detained for the protection of the public.”
Hinton attacked his victims in and around Central Park in Peterborough in the early hours of June 5 last year.
Peterborough Crown Court heard he has been diagnosed with a personality disorder.
But experts decided it was not appropriate to detain him under the Mental Health Act.