He appeared to be the perfect example of a friendly postman.
But Michael Williams' cheery manner hid a dark secret.
In reality he would use his charm to befriend youngsters and then encourage them into sexual activity over the internet.
Williams, 28, of Tresooth Lane, Penryn, Cornwall, admitted 27 charges at Truro Crown Court of inciting sexual activity, grooming and possessing and distributing indecent images.
He had several accounts on social-networking websites to meet and then groom hundreds of child victims.
He used false names, including "Gorgeous Charlie", and put pictures of other men he did not know on his accounts to disguise who he was. He would then often spend four hours a day on the internet, befriending youngsters.
But one 15-year-old girl he befriended on his rounds became suspicious.
She was not one of his victims, but after he chatted to her during his work, he pursued her on the internet.
And to her shock, she later found out he was even using false names on sites such as Facebook as he tried to lure children under his influence.
She said the experience had now left her and her friends scared to go out alone.
'Like a brother'
He had at least seven online identities where he claimed to be teenage boys and girls.
The 15-year-old said she met Williams when he was her postman and that she originally added him to her friends on Facebook under his real name.
But two other online friends also turned out to be Williams using different names. She only found out when she was contacted by police.
She said: "I had these two boys, who turned out to be Michael, that added me as a friend and I always used to talk to them.
"I got very close to one of them. He was like a brother to me, I could tell him everything.
"Then the police told me that they were Michael and it's made me so paranoid and shocked.
"Why would you want to make up some random people and make people believe them?"
She also knew that he asked many of her friends to link to him on Facebook too.
Although she was not abused by Williams, the girl said the experience meant she now never added new friends to her account unless one of her friends could vouch for them.
She added that she and many of her friends in her home town had been badly affected by the case.
'Position of trust'
"It's left all my best mates really shocked," she said.
"We talk about how it's left us, how it's affected our friendship group.
"Now we're too scared to go out. We have to go out as a group in case one of us sees someone who looks like him. It's horrible."
Her father said the fact that Williams was in a position of trust had also shocked the local community.
"When somebody's a postman in your area, you believe in a fundamental trust of that person," he said.
"They're coming to your door ever day with your mail.
"It could be anybody that answers the door, I think he's the lowest thing that crawls."