His trial at Carlisle Crown Court heard that one of his victims complained to police about him persistently harassing her in 2008, three years before his arrest.
During that time he continued his pattern of behaviour in what the prosecution described as a "cold, clinical exploitation of the desperate and vulnerable".
His mode of operation was to target girls and women who he thought would rather have sex for money than risk jail by stealing to feed addictions to drugs or drink.
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