David Cole, 66, appeared to have forgotten about abusing a vulnerable boy in the mid-1990s.
However, the victim said that the predatory Cole “smashed my head” after being stolen from his drink so he could attack him in an incident that he was said to be “terrifying, surprising and undoubtedly damaging.”
His honorary judge, Jonathan Rose, who sentenced Cole to Cole in 44 months in prison, described him as a “devoted and experienced groomer.”
He said: “You stripped him of his sense of worth (the victim).
“You ruined his childhood, and then you ruined his adult.”
Cole, Windsor Road, Bournemouth, Dorset, was extended a three-year prison sentence for supplying ecstasy and cannabis for a terrible indecency crime with a 14-year-old boy in Bradford Crown Court in 2001.
In 2013 he was jailed for three years at Bone Mask Cross Court due to indecent assault and gross involving a 13-year-old boy.
In 2016, he was convicted of 13 charges of raping a child between the ages of 6 and 13, assaulting her indecently, and jailing her for Bradford Crown Court for 12 years.
All crimes occurred when Cole, a former departmental physics teacher, lived in the Kaylee area from the 1990s to 2001.
The latest crimes were revealed when the victim was encouraged to go to the police.
He finds himself charged with abusing another boy after Cole was attacked.
He told police he felt guilty that he didn't report it at the time because he felt that he might be preventing other boys from being abused.
When Cole was interviewed about the incident in 2023, it “caused his memory,” and he admitted they had not mentioned the crimes on previous occasions to the police.
He told the police: “You're right, I remember it now.”
He later pleaded guilty to terrible indecency and vulgar assault.
Cole Judge Rose's imprisonment told him that when you had the opportunity to wipe the slate clean, you didn't take it and so you did “serious damage” to a victim who got lost along the way.
He added: “You finally come to understand that sexual abuse of children is abomination to all those who appear to be right.