The 38-year-old man, who was arrested in the national capital on Sunday for allegedly sexually assaulting hundreds of minor girls, told police he used to "derive fun" out of the act and had his "first prey" in 2001.
Sunil Rastogi also told the police he is superstitious and would travel to Delhi from Rudrapur in Uttarkhand only by Sampark Kranti Express and wore a red jacket every time he came here thinking it was "lucky" for him.
His parents stay in Gharoli area near New Ashok Nagar and he used to come once a week to visit them when he targeted the minor girls, they said.
He was sent to 14 days' judicial custody by a court here.
During interrogation, after he was arrested on January 14, Rastogi said he used to "derive fun" out of sexually assaulting girls aged between 7-11 years, police said.
He used to target minor girls as he thought they could be cajoled and convinced easily and never targeted elder girls since they would fight him off or raise an alarm, they added.
The accused had allegedly "first preyed" on a minor girl in 2001 and thereafter he targeted many girls in Uttarakhand's Rudrapur (where he currently stays), New Ashok Nagar (New Delhi) and Ghaziabad, police said.
They said the accused has has lost count of the number of girls he has assaulted, police said.
Rastogi said he would tell the young girls that their father had sent some clothes or articles for them and if they didn't get convinced, he would pretend to make a phone call to their father, police said.
Sometimes, he also told girls their father had sent him to get them "gold earrings", they added.
An investigating officer said Rastogi used to prey on girls in New Ashok Nagar since he had stayed there and was aware of the "dark and dingy spots", and even the escape routes, where he could assault them, police said.
He wasn't caught till now because he used to come in the morning and leave by the evening.
Many people didn't lodge a complaint for fear of social stigma but after he was caught, several of them came to the police station accusing him of trying to assault their daughters, police said.
Last year, he was arrested in Rudrapur on similar charges and he was out on bail, police said. They said in 2006 also he was sent to Tihar jail in connection with an eve-teasing case.