Passing sentence, Mr Justice Griffith Williams told Sharp: "This is a horrific, cold hearted murder, carried out to gratify your perverted sexual desires."
Sharp, dressed in grey jogging bottoms and a grey jumper, made no reaction but the victim's sister, Emma, sat in the public gallery just yards from the dock, did not take her eyes off the defendant throughout the 50 minute hearing.
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The note - which Flack was advised not to post - has been shared by her family and published in the Eastern Daily Press.