A police officer repeatedly raped a girl from when she was eight years old until she was in her 20s, once telling her: "I can love you more than your puppy ever will", a jury has been told.
The girl was "broken down" by Durham officer Mohammed Perwaze, 45, who controlled her life for years, prosecutors told Sheffield Crown Court.
Simon Reevell QC, prosecuting, said: "By the time she was a young adult, she had quite literally been broken down by this man so he could use her for his sexual gratification because of the sexual attraction he had had for her since she was eight years old."
Opening the case, Mr Reevell said "on the face of it he was a respectable police officer" but described a catalogue of sexual assaults, which included tying the girl to the bed.
He said: "He was clever and he was manipulative. He was violent towards her."
The prosecutor read extracts from emails sent by Perwaze to his alleged victim.
Others said: "I will be the one person still there for you always" and "I love you with all my heart and soul."
Mr Reevell said the girl once told the defendant, as he tried to assault her, that "he was no different to the sex offenders that he arrested at work".
He added: "He remained a serving police officer throughout this period."
The prosecutor said the abuse happened in two phases - the first spanning five years starting when the girl was eight, when Perwaze lived in Yarm, Teesside, and beginning again when she was in her 20s.
Mr Reevell told the jury that Perwaze was also violent towards two young boys from when they were each about six years old.
He said one youngster was repeatedly beaten with a slipper until he could not sit down and punched by Perwaze so hard that he was "not just knocked over, he was sent flying".
The prosecutor said the defendant also threatened to push a knife into the terrified boy's bottom, and would force him to adopt stress positions.
He said this behaviour happened between the ages of six and 16.
Mr Reevell told the jury that Perwaze was arrested after the girl finally decided to complain to police.
He said the defendant made no comment in interviews but produced four prepared statements which "amounted to absolute denials".
Perwaze, of Barns Briar Dykes in Barnard Castle, Co Durham, denies four counts of rape and 14 other charges relating to the girl.
He also denies two charges of cruelty relating to the boys.