SINGAPORE - A company director, 47, who raped an underage girl who was his son's former girlfriend was sentenced to 20 years' jail and 15 strokes of the cane on Thursday (July 12).

A High Court judge said the man had, over a protracted period, taken advantage of the "innocence and helplessness" of a young girl and had no qualms about causing her emotional damage to satisfy his desires.

While Justice Lee Seiu Kin accepted that there was no physical violence involved, he said the man's behaviour was "predatory" and "manipulative", noting that he was "old enough to be her father".

The man cannot be named to protect the identity of the girl.

In March, he admitted having sexually abused the girl over a period of 1½ years from December 2012 to May 2014 , when she was between 11 and 13 years old.

He pleaded guilty to two charges of statutory rape and one charge of sexual penetration of a minor. Fourteen other charges were considered during sentencing.

The court heard he was accessing his son's Facebook account in December 2012 when he found nude pictures of the girl. The Primary 5 girl had sent the images via private message after the Primary 6 boy asked for them, the court heard.

The man contacted the girl and sent her the pictures, saying he wanted to meet her to talk about her break-up with his son. On Christmas Eve, he drove her to Copthorne King's Hotel and raped her in a room he had booked.

Initially, she felt angry about the rape and feared that he would spread her nude pictures.

However, she grew to like the man, who told her he loved her, encouraged her and showed concern for her.

She continued meeting him for consensual sexual acts in carparks, hotels and the rooftop of her condominium.

When she turned 12, he drove her to a deserted carpark, gave her birthday presents and asked her to perform oral sex on him.

The man also took pictures of their sex acts with his mobile phone and asked her to send him pictures of herself in sexually provocative poses.

In February 2014, she wanted to end the affair after getting into a relationship with a teenage boy, but the man refused to break up with her.

Using prepaid SIM cards, he posed as mysterious men and sent her messages threatening to post her naked pictures online. Unaware that he was responsible for the messages, she turned to him for help.

He also contacted her friends and used her naked image as the profile picture of a WhatsApp account.

This led to his undoing. In July, a parent saw the profile picture in a chat window on his daughter's phone and recognised the victim.

Defence counsel Anand Nalachandran sought 12 to 15 years' jail, highlighting that his client had indulged in extramarital affairs as a mechanism to cope with stress at work and at home.

Deputy Public Prosecutor Ng Yiwen argued for 21 years' jail and 24 strokes of the cane, arguing that the man had no genuine feelings for the girl at all; rather she was just an "easy target" that he treated as a sex object.