He was her social studies teacher. And she found him funny and witty.
But he took advantage of that and groomed Sarah (not her real name) for months to satisfy his sexual desires.
Eventually, he was found out.
He married her to stop her parents from calling the police.
But in the end, he ditched her for another woman.
Now 21, Sarah is divorced and a single mother to a five-year-old boy.(We are not revealing her identity as there is a strict patient confidentiality clause and we conducted the interview through her counsellor.)
We wanted Sarah to tell her story so she could throw light on what it is like being the target of a sexual predator.
Psychologists and counsellors we spoke to say a crucial step in sexual grooming is gaining the trust of the victim before abusing it. (See report on facing page.)
Last week, a former Straits Times reporter was jailed 18 months for having underage sex with a 15-year-old student.
Eisen Teo Guan Kuan, then 27 and recently married, had sent Whatsapp messages to the victim, which grew increasingly sexual in nature. He later had sex with her several times and once in his home - when his wife was baking in the kitchen.
For Sarah, our victim, it also started when she was 15.
"I was attracted to him because he taught well. He was also a very humorous guy," she says.
She feels that the teacher, who was married without kids and in his 30s then, paid more attention to her in class.
"Because I am pretty, I guess," says Sarah, who describes herself as tall and slim with big eyes.
It started with SMSes from him showing concern.
She says: "I was flattered that he cared so much about me. I told him about my family problems."