Magician David Payne told a jury he hoped he had not ruined the rest of the life of a girl he is accused of raping.
The 56-year-old admits he indecently assaulted the youngster, now aged ten, on four occasions when she was aged seven and eight.
And the entertainer, who advertises himself as a member of the Magic Circle, choked back tears as he told the jury of six men and six women how he finally realised that what he had been doing was wrong.
He said the eight-year-old girl and her father had come to his house in Burton near Chippen-ham so that she could apologise for misbehaving on a previous occasion.
Speaking from the witness box the balding magician, who moved to Wiltshire from Saudi Arabia 12 years ago, said: "It had a sobering effect. Her father brought her to the house and I just happened to be there. I answered the door.
"He stood there with his daughter beside him, being the responsible adult I had failed to be. I had in the past but had not maintained it and it shamed me."
The jury had been told by the girl that she stopped the abuse when she realised it was wrong after he raped her.
Payne strongly denied the rape. Asked about what he thought of his conduct he said: "Appalling. I am thoroughly ashamed and also very profoundly sorry.
"My thoughtlessness and irresponsibility had ramifications. I think the jury saw the effect it had on her mother and father."
He told the jury at Swindon Crown Court that he had indecently assaulted the girl four times, possibly more, over a period from March 1997 to June 1998.
Payne denies rape and indecently assaulting two other young girls.
The case continues.
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