Realising that the girl he was about to pay for sex was underage, Qiu Wenbo tried to get round the law by obtaining only oral sex from the 17-year-old and running off without paying.
But it cut no ice with a district court judge and the 28-year-old, also known as Allan Khoo Wenbo, was Monday given a six-month jail sentence for the offence.
He is the 27th man to be punished for having paid the same girl for sex, in a long-running online vice-ring case. Altogether, 51 men were charged last year.
Deputy Public Prosecutor Elizabeth Chua had wanted at least a nine-month jail term for that offence, arguing that Qiu had deliberately tried to evade the law.
But Qiu's lawyer, Mr Sunil Sudheesan, in asking for four to five months' jail, said his client was sorry for what he had done.
On Dec23, 2010, Qiu contacted the girl's pimp and agreed to pay $650 for her sexual services, to be performed at Strand Hotel in Bencoolen Street.
While the girl was taking a shower, Qiu checked her identity card in her wallet and realised she was underage.
Aware of the law on having paid sex with a girl under 18, he asked for and received only oral sex and intentionally ejaculated on her body. While she took another shower to clean herself, he fled.
The maximum penalty for the sex offence is seven years in jail and a fine.
On Monday, Qiu was also given a one-month jail sentence for two unrelated charges.
In all, he received a total of seven months' imprisonment.
He pleaded guilty to the sex charge as well as to two charges of using another person's identity card to enter the Marina Bay Sands casino in December 2011.
One charge of entering the casino without paying a levy was taken into consideration.
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