Image copyright Getty Images

Troye Sivan has revealed he cried and felt "really sick" the first time he felt attracted to a man.

He told Attitude magazine: "I remember I cried when I realised that I thought Zac Efron was really hot, aged 13 or something like that."

The 22-year-old singer also spoke about his current boyfriend, model Jacob Bixenman, and gave his thoughts on monogamy.

Since coming out in 2013, the pop star has been an avid LGBT campaigner.

South African born Troye Sivan revealed he was gay in a video he posted on YouTube five years ago.

Since becoming a well-known musician he's used his influence and status to deliver the prominent message of people being comfortable with they are.

In 2016, he won the outstanding music artist at the GLAAD awards, which recognise people for their "fair, accurate and inclusive representations of the LGBT community".

He's currently dating model Jacob Bixenman and told Attitude magazine he's written songs about him.

"He's got like a kind of energy about him, a magnetic sort of energy," the singer said.

"I think people can't help but love him. He's just got one of those personalities that draws people in."

He added: "(We started dating) pretty much since the day that I met him. We have seen each other almost every day, unless I've been travelling or something.

"It's kind of like having your best friend around all the time, which is really nice."

Relationships are a large part of his lyrical content and he admits his parents are a huge inspiration.

Image copyright Getty Images Image caption Troye Sivan and his boyfriend Jacob Bixenman in Los Angeles

"My parents have been married for 27 years, or something like that, and are more happily married than ever, and so that's kind of my reference point. It and just feels right to me."

Troye is scheduled to release his yet untitled second album later this year.

"I think I'm monogamous by nature and I really enjoy that. Maybe I can be a jealous person and, I don't know, it just feels what's right for me."

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