"I am a lost boy from Neverland... hanging out with Peter Pan."

Played over some simple chords, those were the six seconds of lyrics that Canadian singer Ruth B posted on Vine in 2015.

It proved so popular that fans demanded she turn the song into something bigger.

"I built on it, adding a new line every day so that eventually I had the song that I posted on YouTube," she tells Newsbeat.

The song became Lost Boy, which went on to reach number 24 in the US Hot 100.

In a US chart full of pop, EDM, rap and country, it's unusual to see a simple piano ballad doing so well.

"Every day I have to remind myself that this is not a dream," she says.

"This time last year I was a student just trying to figure life out and now I'm travelling the world singing and writing songs."

The song is about being immersed in the world of Peter Pan and came about after she was watching US fairy tale series Once Upon A Time.

"I went down to my keyboard and was playing random chords and the one line I kept repeating was, 'I'm a lost boy from Neverland.'

"I decided to post it to Vine and it got the biggest reaction I'd ever gotten. People wanted to hear more and I had to explain it wasn't a song.

"When I sat down to write it I wanted to make it as relatable as I could. Everyone's been lonely at some point and in need of a friend."

That was early in 2015. The 21-year-old's now signed to Columbia Records.

However, the studying had to go on hold.

"I was a political science student. I had a nice talk with my parents and told them I was going to give singing a go. I will go back to studying but I'd love to get a degree in writing."

Ruth, who's from Edmonton in Canada, is now working on a debut album and insists she's more than just a one hit wonder.

"I have 24 songs in the bag. I do 45-minute sets at gigs and it's all original stuff. I don't find the writing challenging. I grew up loving writing stories and poems."

She also says she's a huge fan of Ed Sheeran who she calls "inspiring".

"His album + (Plus) played a really big role in my understanding of music. It was one of the first times I heard a body of work and I felt that I got it. I want to make people feel the way that album made me feel."

Ruth says those early days on Vine are still important to her career now.

"Vine played a huge part in my creativity level. I wanted to make sure they were the best six seconds they could ever be so.

"Now in my song writing I want every line to be the best line it can ever be."

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