Debris Stevenson’s first public performance, at the age of 15, sounds like an impetuous act of courage. For years she had been bullied, but she found herself at the school disco emboldened enough to “grab the mic”. The lyrics poured out of her. “It should have been scary but I was full of adrenaline. Whether it was good or not I couldn’t tell you.”

Until then, she kept the grime poetry she’d been writing in the library and “spitting out” on the way home from school secret. She often sat in the library and watched the world go by, struggling with dyslexia and tormented by trying to square her queer sexuality with her parents’ strict Mormonism.

It was grime that got her through those desolate days, says Stevenson. The music that was fomenting in the housing estates of east London as she was growing up in her working-class home in Ilford gave her access to language and poetry, and a sense of belonging: “There was something about the rage, something about the honesty, something about the locality. It was being made by people of not a dissimilar age to me. My home life had been all about my parents’ Mormon church. It wasn’t working for me and I needed a new home.”

Facebook Twitter Pinterest Jammz, Debris Stevenson, Cassie Clare and Kirubel Belay in Poet in da Corner. Photograph: Tristram Kenton/The Guardian

She documented it all in a semi-autobiographical grime musical, Poet in da Corner, which was staged to great acclaim – and some astonishment – at the Royal Court in London last year. Named after Dizzee Rascal’s seminal 2003 album Boy in da Corner, it crackled with the hybrid urban sounds of the genre and incandescent poetry. Such was its impact that the Royal Court permanently installed a bigger, better sound system on Stevenson’s recommendation, and the show is returning in January.

Stevenson, at 29, is firmly ensconced in the grime scene as a poet, playwright, singer and dancer. She is currently in rehearsals with her new play, 1st Luv, which again incorporates grime music and poetry into its themes. The play is being directed by Ned Bennett – whose confrontational productions of An Octoroon and Equus stunned audiences – and staged at the Big House, a theatre company that works with young people leaving the care system. While its focus is on emotional support and personal empowerment, the company has launched the careers of actors including Jasmine Jobson, from the TV series Top Boy, who is set to star in the 2020 thriller Surge alongside Ben Whishaw; and Aston McAuley, who appeared in the TV drama Endeavour and the Elton John biopic Rocketman.

As someone who might have been deemed “at risk” when she was younger, Stevenson wanted to stay away from well-worn narratives about troubled teenagers. “I see a lot of stories in which they are entangled with drugs, violence and gangs. I love a lot about Top Boy but I think, ‘What other stories are we going to tell?’”

So she wrote a “celebration of love and music”. 1st Luv is a play about children experiencing the first sparks of romance, but also dealing with the traumatic inner drama of being in care. “I wanted to capture that age when you are between childhood and adulthood. It’s an exciting period, but we get into the darker stuff, too, because the reality is, if you are put in care, something difficult has happened around your formative experience of love.”

Facebook Twitter Pinterest Cassie Clare and Debris Stevenson in Poet in da Corner. Photograph: Tristram Kenton/The Guardian

To the outsider, Stevenson cuts an unusual figure as a woman in a music scene dominated by men. How much of an anomaly is she? And can she own a slang word like “skank”, with all its insinuation of female promiscuity, and not feel diminished by it? Yes, she bats back instantly, and the cast of Poet in da Corner did workshops to unpack this very subject so that everyone felt comfortable with the language. More women are emerging on the grime scene, she adds. “People can disagree with me, but I think most women in grime are queer. A few MCs have come out recently. You’re getting more female MCs who are starting to put it into their lyrics now.”

As for the way she feels as she pursues her passion for the music, she says: “I’ve gone to raves all around the world on my own. A lot of those have been grime raves, and thinking about how people interact with me, how I can own space but how that space is squashed – it’s a really complicated dynamic.”

What infuriates her about the conversations about women in urban music are their reductive, racist undertones. “I remember a Cardi B song called Twerk. There were loads of girls twerking in the video and there was massive uproar online. When I saw it, I actually cried because I saw women dancing for each other and doing incredibly skilled things. Often if you’re a woman, often if you’re a black woman, people stop talking about the skill completely – they just hyper-sexualise you. Similarly, people are reductive around grime. When anything comes from within black culture, it is hyper-reduced and hyper-criticised. It’s horrendous.”

Being a white woman in grime also has political undertones, which Stevenson addressed in Poet in da Corner by exploring authenticity and appropriation. In the early days, she says, people got her race confused, not seeing her as white. She was also, conversely, challenged for inhabiting this cultural space. But she was right to be challenged, she says. “The reality is that there is currency in the fact that I’m white that will get me attention and traction, and it’s my responsibility to acknowledge that. When an opportunity is presented to me, it’s my responsibility to question, ‘Why am I getting this?’ TV companies have asked me to show them around bashment raves and I’ll say, ‘Who else are you talking to because I’m not from Jamaican culture?’”

I love a lot about Top Boy but what other stories are we going to tell?’

It is, she says, white, middle-class spaces where she has experienced greater degrees of alienation. Stevenson was recently referred to as “common as muck” by a TV executive (“He thought it was a joke”), and says that many in media and performing arts confuse race with class: “People assume that if you’ve covered race you’ve covered class. My partner is mixed race and middle class, but people assume he is working class. So things get compounded in a way that is very problematic.”

Fictionalising aspects of her childhood and the formative people of it for Poet in da Corner has clearly not put her off treading the sensitive ground between art and life. There are other plays she would like to write that spark off life, including one about her best friend, whose parents were Hells Angels (“She works at JP Morgan now”). There is also the story of her older brother, who was Citibank’s highest-grossing trader when he was 23. He retired at 27 and has since done a master’s at Oxford University. Her other brother sounds just as extraordinary: he taught himself how to build super-computers from components he found in skips.

So what did her parents make of Poet in da Corner when they saw it? “They didn’t see it. Their 35th wedding anniversary was during the run and they were away. My brothers think they did it strategically, but I haven’t properly come out to my parents, and it’s quite traumatic whenever I have tried. I don’t want to have to do that live on stage with them.”

If pain remains, there has been some recent catharsis too; Stevenson’s parents came to see her perform a set for the first time last month. “It was at Redbridge library in Ilford, and I did a set that was church-appropriate. My mum was sitting in front of me and I couldn’t look at her because she cried the whole time. They both seemed proud.”

• 1st Luv is at the Big House, London, from 20 November to 21 December. Poet in da Corner at the Royal Court, London, from 30 January to 22 February. Then touring.

• This article was amended on 7 November 2019 because an earlier version misnamed Citibank, as City Bank. This has been corrected.