Matthew Kelsey, 32, who has been jailed for two years, twice had sex with his victim after travelling 270 miles to Stirling from his home in Yorkshire.
The girl’s mother has now warned other parents to be careful about who their children are meeting online.
She said Kelsey’s instructions to her daughter, who is now 15 and struggling to cope with the abuse she suffered, “would have turned anyone’s stomach”.
The mum, from Stirling, said Kelsey had given her daughter 20 rules she had to abide by to be his girlfriend.
She added: “I gave the list to the police and can’t remember all his rules, but they included orders like, ‘You must call me Daddy’; ‘When we speak on the phone you must use a baby voice’; ‘When you take a shower, you must FaceTime me’.
“It made me remember that at times we thought we’d heard her talking on her phone when she was in the bathroom and I was worried about what was going on, but she always told me I was wrong.
“After we learned the truth, I saw messages including one he sent her saying, ‘Daddy wants a picture.’
“My daughter had refused and he said that if she didn’t do what he wanted, ‘Daddy’ had other girls who would do it for him.”
The mother added: “My daughter was vulnerable, having been bullied at school, and he had tapped into that and made her feel special, telling her she was beautiful, talking about being depressed and lonely himself, saying he loved her.
“It is very easy for a grown man to appeal to a lonely teenager.”
In March last year, Kelsey contacted the Scots schoolgirl after she bought a gaming app.
He had set up a Facebook profile in the name “Alan Thomas” and gave her pet names such as “Pumpkin” and
Within five months of the first introduction, he had sexual intercourse with the girl.
Her parents knew she was talking for hours to an English friend, but she told them he was 15.
Her mother said: “She told us that his granny lived in our town and he was coming to visit her in August last year so she would get to meet him.
“We were keen to meet him as well, because it was obvious they had become close online, but he kept his distance.
“At one point, he had chummed her home but wouldn’t come to the door to say hello.
“He played shy and waved at me from a good distance so I couldn’t see how old he looked.
“One day when she was with him, I called her to ask where they were and she said they were in the park.
“I told her to stay there as her sister was on her way to join them and say hello. She waited for her sister, but he fled.
“He clearly didn’t want any of us to see him.”
Kelsey made the trip in a van that he had kitted out with a bed in the back.
He took his victim to a rural setting – where he carved their initials on a tree – on at least two occasions, luring her into his van because it was raining, kissing her and touching her intimately the first time.
On the second occasion, he had unprotected sex with his victim twice, showing no regard for her safety.
He then planned a second visit in January this year.
On this occasion the girls’ parents insisted on meeting him.
Her mother said: “He did his best to avoid us again but I told my daughter she wasn’t seeing him if we didn’t get to meet him.
“He came shuffling in, looking at his feet, and her dad and I just looked at each other.
“I said to him, ‘You don’t look like you’re 15 to me.
“You look like a dirty paedophile who has been grooming my daughter.’
“He tried to insist he was 15, but I pointed out his five o’clock shadow, and he hurried out the door.
“My daughter was upset and went after him.
“I phoned her and she said to me that Matthew had admitted he was 19.
“I told her he was not 19 either and to get back inside.
“He knew we were going to call the police and set off back down the road to Yorkshire, but he kept on talking to my daughter as he made the journey, and that helped the police locate him.”
The mum added: “He was also generous to her.
“He sent an expensive present for her at Christmas and even sent presents for her siblings.
“They were just cheap toys from bargain shops but that actually made it look plausible that he was just a young boy.
“We were more curious about how a boy of 15 could have afforded the expensive present, a gold and silver bracelet inscribed to his ‘Queen’.
“But my daughter told us his family ran a car firm and he had been helping out part-time.
“When we set eyes on him, we knew there was no way he was 19, never mind 15, and had to call the police.
“My daughter is safe from him now but the damage has been done.
“We feel one of the best things we can do is to warn other young girls and parents that this guy will soon be free.
“He travelled more than 250 miles to get to my daughter, so everyone needs to look at his photo, get to know his face and make sure that if he approaches them, they keep well away.”