He admitted in court in January to sexually violating 31 underage boys over three years.
But before handing out his sentence yesterday, Justice Woo Bih Li felt that Yap Weng Wah's plea of guilt "did not spring from genuine remorse" but came "from a realisation that his goose was as good as cooked".
Justice Woo noted that when Yap was first interviewed by the police, he had lied by saying that he engaged in oral and anal sex with only three boys.
Justice Woo added: "Yap's attempt to downplay the extent of his offences leads me to conclude that he was not genuinely remorseful for his actions.
"This is the worst case of sexual offences against pubescent males."
The 31-year-old quality service engineer was yesterday jailed for 30 years and given the maximum 24 strokes of the cane. The Malaysian, who came to Singapore in 2009 to work, pleaded guilty on Jan 16 to 12 counts of sexual penetration of minors.
Another 64 charges were taken into consideration during sentencing.
Yap committed the offences between Nov 6, 2009, and June 30, 2012. All the sexual acts were performed without a condom.
The boys, who were between 11 and 15 years old, were made to perform acts ranging from kissing to anal sex.
Yap would trawl the Internet, looking for boys who lived or who went to school near his rental apartment in New Upper Changi Road and later in Yishun.
He would befriend his targets on Facebook. When they met, Yap would usually pay for meals or movie tickets.
He would then lure the boys home on the pretext of playing video games or to retrieve an item before sexually assaulting them.
He also violated the boys at public places, such as toilet cubicles in shopping centres and swimming complexes.
Yap recorded the sickening episodes with a camera or his mobile phone.
In some of these cases, his victims were aware that he was filming them. But when they protested, Yap would assure them that he would delete the clips later.
His crimes came to light after the sister of an 11-year-old victim found text message exchanges between Yap and her brother.
After his arrest on Sept 7, 2012, officers from the technology crime and forensic branch examined his laptop and found about 2,000 video footages of him performing sexual acts on various people, including the boys here.
There were also videos involving at least 14 other boys, made during his annual visits to Malaysia.
Yesterday, Justice Woo said that Yap has hebephilia, a sexual preference for early adolescent children generally aged 11 to 14.
He said: "I hope he truly overcomes his deviant interest in young boys."
For each count of sexually penetrating a boy under 14 years old, he could have been jailed up to 20 years, and fined or caned.
Number of years the 31-year-old quality service engineer was jailed yesterday. He was also ordered to receive the maximum 24 strokes of the cane.
This article was first published on Mar 21, 2015.
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