Rina Sawayama: Therapy made me realise I was groomed at 17

"I've never talked about this in any other interview," Rina Sawayama says, her voice steady.

She keeps eye contact, ready to share the painful inspiration behind her second album, Hold the Girl, which she wrote after several sessions of sex and relationship therapy.

A few hours from now she will command the rooftop stage at New York's Pier 17 venue, performing to a sold-out audience.

The crowd is not just made up of teenage girls, the usual staple that dominate audiences for pop starlets. Several same-sex couples are here, swaying and kissing to the more anthemic songs and a group of trans women mouth along to the LGBT-inclusive This Hell.

The team and tour crew that surround Sawayama are all just as diverse.

"The heads of the music industry are still a lot of straight white men," she says, "so I work with people I want to see more of in the industry."

Sawayama has been touring internationally for several months.

This has been a significant year for the artist. She performed her own set at Glastonbury 2023, followed by an appearance alongside Sir Elton John on the Pyramid Stage. She featured on the cover of British Vogue's LGBT-pioneers issue. And she starred in her first Hollywood feature film, John Wick 4, alongside Keanu Reeves. It's all been part of her steady rise to fame.

In 2021 the Japanese-passport holder, who has lived in the UK most of her life, successfully spearheaded a movement to change eligibility rules for the Mercury Music Prize and Brit Awards. Now, non-British UK residents can qualify for the big prizes.

Since then she has released two studio albums and has been performing continuously ever since coronavirus restrictions were lifted.

New York Pier 17 is her final performance before a break in the tour.

A few hours before her show, inside a chic hotel, with the intrusive noise of New York's East Village whirring outside, Sawayama is about to share something for the first time publicly - the inspiration behind her album, which NME music magazine describes as a "total triumph".

It is about a relationship with an older man, she says.

"I was groomed," she tells the BBC: "It was by a school teacher."

Sawayama was 17 at the time. She says that's a time when a girl is often making choices she isn't ready for.

Now, aged 33, Sawayama says she looks back on that period of her life with defensiveness for her younger self.

"Seventeen to me is a child. You're in school. If a school teacher is coming onto you, that's an abuse of power," she says. "But I didn't realise until I was his age."

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Sawayama admits that she felt "slut-shamed" by her peers for the relationship, and its aftermath led to a long period of self-loathing.

"I completely lost my sense of self," she says. "I dissociated from my body. I just felt so afraid."

She says sex and relationship therapy allowed her to rethink what happened from an adult perspective.

"I would revisit my 17-year-old self, hold her close, and tell her that it wasn't her fault."

It was the inspiration of the album title Hold the Girl and her other songs went even further.

Your Age, the seventh song on the album, is about reaching the same age her teacher was at the time and realising how wrong it was.

When it was released, critics described the industrial, nu-metal inspired track as "angry", with Paste magazine saying it was like "a long-dormant volcano exploding". Lyrics such as: 'Why did you do it? What the hell were you thinking?' speak to a visceral pain that still exists within her today, over a decade later. But some critics incorrectly guessed the inspiration for the song was about a lack of connection with her immigrant family.

Born in Japan in 1990, Sawayama and her family moved to London when she was five years old. The initial plan was to return to Japan, but when they were eligible for a permanent visa, Sawayama's mother decided that her creative and expressive daughter may be better suited to a city like London.

Sawayama entered the music industry relatively late, in her mid-twenties, years after completing a politics and psychology degree at Cambridge University. She was 27 when she signed to a record label, and she felt uncomfortable about her age.

"When I was growing up, especially in the 1990s and 2000s, you signed to a label when you were 13, 17 at the oldest," she says, referencing female pop stars she looks up to, like Britney Spears who was just 15 when Jive Records gave her a contract.

"I was 29 when my first album came out, so I felt old."

But she was embraced by a young and diverse fanbase. Sawayama, who says she is attracted to people regardless of their gender, came out as pansexual in 2018. Her videos rack up millions of views and attract comments praising her for singing about social issues.

The video to Sawayama's first single STFU! is an outcry against microaggressions many East Asian women experience in western countries. It shows Sawayama on a date with a white man, who makes a series of racially inappropriate comments, and at one point narrows his eyes using chopsticks to pull them apart. The song, she says, was inspired by personal experience.

"I felt people saw me as a map of Japan, not as a person," she says. "I think a lot of immigrants, or first generation immigrants, can relate to that."

STFU! went on to be named as one of the best songs of 2020 by Rolling Stone magazine and while Sawayama still remains a refreshing addition to mainstream pop, she's not shy about pointing out its failings.

"There's a lot of people outside of the music industry, who don't know about the music industry," she says. "Recording artists don't have exit clauses between albums, for example."

"There needs to be some sort of overhaul, because currently it's very much benefiting music labels and record labels, and not artists."

So is it a worry to speak so honestly about the industry she is still navigating?

"I have always wanted to lead with the truth, always," she stresses, "being transparent is important to me".

It's in that spirit she says, that she now wants to share with fans her story and the trauma that inspired so much of her recent music.

"Writing that album was one of the hardest things," she says, "but it was also one of the most incredible experiences".

Incredible, because of its impact.

Back at Sawayama's rooftop concert in New York, you can see how the song Hold the Girl, in particular, clearly shakes the audience. At the front row, where the most hardcore fans stand, several are in tears during her energetic performance. Although they may not know yet the full meaning behind the song, it evidently moves them.

"When I look out to the audience and I see women or femmes connecting to it, I think maybe you know," Sawayama says. "Maybe you have experienced this too."

When it comes to her future work, Sawayama admits she's not sure what kind of songs will make up her third album: "I hope that I don't have to write autobiographically all the time!"

"I don't want any more traumas to come out," she acknowledges, as she smiles wryly.

"I would love a day where I can write a song that's just about love or sex," she says, adding: "I'm getting there. I am getting there."

In Conversation is a collaboration between the BBC World Service and BBC Three.