Vile Anthony Morgan, 41, admitted the sexual assaults were part of a “campaign of rape”.
Liverpool Crown Court heard him admit to raping his victim on no fewer than 225 occasions.
You repeatedly raped almost week in, week out that young girl
Judge Menary said: “You repeatedly raped almost week in, week out that young girl, on too many occasions to count.
“What you have done to this girl is to essentially ruin her life up to this point.
“Who knows whether or not she will ever recover from the psychological ordeal and impact you have inflicted upon her.”
The court heard that he would offer the victim treats in exchange for sex.
Dan Travers, prosecuting, told the court: “He would ask her to have sex and when she refused he would keep asking. He would eventually get angry and just do it anyway.
“It’s difficult to envisage a more serious campaign of rape.”
Morgan – also known as Anthony Murphy – admitted eight counts of rape and one count of attempted rape.
The girl has since struggled with education, suffered emotionally and physically and sustained “severe psychological trauma”. He denied raping the girl no less than 60 times, when she was aged just four and five.
The judge told Morgan: “You accept you have an unhealthy and abiding sexual interest in young children.
“I have no doubt at all that you pose a high risk of serious harm to children and will continue to do for an indefinite and unquantifiable period in the future.”
Morgan will serve at least two thirds of his sentence in jail and will only be released if a parole board deems it safe.