A paedophile who groomed and abused six boys over a four year period has been jailed for 10 years and nine months.
David Jamfrey, 60, lured boys as young as five to his flat and gave them cigarettes before assaulting them.
He was jailed at Sheffield Crown Court where Judge Sarah Wright said his "persistent grooming" had "shattered the lives of his victims".
Jamfrey of of Middlegate, in Scawthorpe, Doncaster, pleaded guilty to 17 sexual offences.
Judge Wright said: "You groomed these young boys, allowing them to spend time at your flat, encouraging them to watch TV and use your computer, and you gave them cigarettes so you could gain their trust in order to then exploit them.
"You groomed them to such an extent that when one of the boys was first interviewed he made no disclosure in relation to your conduct and in fact defended you and your actions."
Jamfrey abused the boys, aged between five and 15-years-old, between January 2010 and May 2014.
'He stole my childhood'
During the investigation police uncovered Facebook messages sent between Jamfrey and one of the boys in which he offered to give the boy cigarettes if he would let him perform a sex act on him.
Prosecutor Gordon Stables said the messages were "the plainest evidence of the effects of the grooming and the control exerted" by Jamfrey and "the way in which he got in to their minds and was using cigarettes and other things as incentives for him to be able to offend an obtain their compliance".
In a victim impact statement read to the court, one of the boys said: "Because of this monster, I will never be a typical 14 or 15-year-old. He stole my childhood and he stole my innocence."
Jamfrey pleaded guilty to 11 counts of sexual assault of a male under 13 and four counts of sexual activity with a male aged between 13 and 15.
He also admitted one count of engaging in sexual activity in the presence of a child under 16 and one count of attempting to engage in sexual activity with a child.