In 2020, early in her career, South Korean-American musician Kim Eun-jae, known as Ejae, joined the small songwriting team for a new animated film project, KPop Demon Hunters. She ended up co-writing some of the film’s biggest hits, including Golden, Your Idol, How It’s Done, and providing the singing voice for its protagonist Rumi.The film, released in June 2025, became, quite simply, a global phenomenon: I tell her that Golden has been played in our house and in our car every day for a year, thanks to my five-year-old’s obsession with it. “I’m sorry,” Ejae says, giving a small smile. But no wonder she’s smiling; Ejae’s life has been a whirlwind of fame, adoration, accolades and red carpets ever since the film came out.Today, we’re in Paris on the set of Ejae’s photo shoot. Yesterday she was sitting in the front row at the Dior couture show (she is an ambassador for the brand). She attended the Golden Globes in January, the Grammys in February (taking home awards for Golden at both) and the Met Gala in May. She sang at the opening of the World Cup in June (a song she co-wrote for the tournament, naturally) and performed at this year’s BAFTAs, Brit awards, Coachella and the Oscars, where she scooped the best original song award and discovered that Beyoncé and Jay-Z are mega-fans.“I was at their after party and Jay-Z came up to me and said, ‘Hi, my name’s Shawn,’” says Ejae, 34. “I was beyond starstruck. Beyoncé is my idol and she said, ‘You have an incredible voice.’ I asked her, ‘Do you know Golden?’ She was like, ‘Yeah, my girls sing it.’” Ejae pauses, wide-eyed, and adds: “And her daughter’s name is Rumi.”Blending comedy, action, fantasy and music, KPop Demon Hunters, an American animation drenched in Korean characters and pop culture, is about a girl band called Huntrix – Rumi, Zoey and Mira – who sell out stadiums while secretly fighting demons that feed on human souls.Rumi, Zoey and Mira are voiced by actors, but their singing voices come from Ejae, South Korean-American singer Rei Ami (Zoey) and American singer Audrey Nuna (Mira). The trio have become best friends, having performed together countless times.Ejae describes Golden as the film’s Let It Go, a pivotal moment in the Disney film Frozen and another song that went viral. Golden is a certified pop banger about self-empowerment, self-belief and the power of female friendship. If you’re a parent of a young child, you will not have been to a kids’ party in the past year at which Golden wasn’t blasted out over the bouncy castle.Six weeks after the release of KPop Demon Hunters, Netflix announced that it had become the platform’s “most watched original animated film of all time”. Five months later, it became the most watched original title in Netflix history and has gone on to rack up more than 628 million views. Google search data revealed that Rumi was the highest-trending Halloween costume idea in 2025, about the same time the soundtrack album was certified platinum in America, and Golden has topped the charts in more than 30 countries. Unsurprisingly, a sequel and a tour have been announced.Ejae wrote Golden, the hit track from KPop Demon Hunters that has been No. 1 in 30 countries.© Ward Ivan Rafik/Headpress“I know [this kind of success] happens, I just didn’t think it would happen to me,” Ejae says. “I had no inkling at all that KPop Demon Hunters would be as big as it became. I did think it might be, because the story is so cool, but you never know. In the past year, I’ve lived five lives. It doesn’t stop. Who does this all in one year?”Ejae wrote on Instagram in April that “being an Asian-American woman in the music industry is not easy”. I ask what she meant by that. “I don’t see the representation,” she replies. “I’m not going to lie, there’s definitely some level of racism. Definitely stereotyping. Especially women. I am genuinely curious why. But if you have one person who looks like you in that industry, it feels easier to get into that industry, right?”Kim Eun-jae was born in Seoul. Her mother is Korean, her father Korean-American. The family (she has an older brother) lived in New Jersey, but her mum wanted to give birth in Korea. Then, when Ejae was six months old, the family moved back to America. Her parents divorced when Ejae was eight and her mother moved the kids back to South Korea. “My mum had custody of us and raised us as a single mum, so she wanted to be near her parents,” she explains.In South Korea, Ejae attended an American school and at the age of 11 started after-school and weekend lessons at SM Entertainment, an influential K-pop record label and entertainment agency that has produced artists such as the girl groups Aespa and Red Velvet.“They teach you how to be a pop star,” Ejae says. “Singing, different kinds of dancing like jazz, contemporary, hip-hop and ballet to improve your posture, public speaking and interview training. Every month they would take you to do a photo shoot so you could learn how to pose. We did a ton of languages. We learnt Chinese because they knew China would be a huge audience.”But there were darker aspects too. “They didn’t like us to ‘kimchi squat’.” She gets off her stool to show me. “Because it made your knees ugly; it ruined your knees. We couldn’t chew gum because it would make our jaws bigger. We would have to smile in front of the mirror with a ChapStick here” – she demonstrates a pout as if a small tube of lipstick could rest between your upper lip and your nose – “because it makes your muscles grow and your face shape [better]. We couldn’t have ear piercings. It was very much no sodas, no greasy food, keeping yourself unbloated and fit.Ejae provides the singing voice for the character of Rumi in the KPop Demon Hunters film.NETFLIXI wouldn’t say it was healthy. Let’s just be real. It’s very ambitious for a teenager.”Still, she was there for 11 years. Did she enjoy it? “I don’t know if ‘enjoy’ is the right word. Did I work my ass off? Yes. Did I learn a lot? Absolutely. Was it difficult? Yes.“But did I think it was worth it? Yeah, because my dream was to be in music and it is a system that will help you become a global star. Even today, when I’m posing in front of the camera I don’t feel awkward because I had it ingrained in me as a kid. I’m not shy in front of the camera. I’m shy about performing because I’m a perfectionist.”Aged 21, while she was studying at music college in New York and still signed to SM, Ejae discovered SoundCloud and became “obsessed with making beats – I got all this equipment.” Two years later she was dropped from SM. “That was depressing,” she says. “We didn’t match artistically. My voice was too low. They liked more feminine, clean vocals.”Figuring out her next move, she started meeting producers. One invited her to a studio, played her an instrumental track and asked her to try writing lyrics for it. “I’d never written a proper song. They said, ‘Write about whatever you want.’ So I wrote about my boyfriend at the time because we’d had a huge fight that day.”The song became Hello and was picked up by the South Korean singer Hani. Ejae then met Andrew Choi, a singer, songwriter and fellow SM veteran who became her mentor and later voiced Jinu, the male lead in KPop Demon Hunters.Ejae (centre) with her KPop Demon Hunters co-stars Rei Ami (left, who voices Zoey) and Audrey Nuna (Mira).WWD via Getty ImagesIn 2019, another song she’d co-written, Psycho, was picked up by Red Velvet and topped the Billboard world digital song chart. “That’s when I was like, OK, maybe I do have a skill set for this, let me take this really seriously.”Months later she was invited to work on KPop Demon Hunters. She sang the demos she’d written for the film and the directors asked her to sing as Rumi. “I never thought I would be an artist,” she says. “I didn’t have thick enough skin. I was very sensitive in my 20s; I can’t handle criticism.”So what does Ejae’s future hold? She doesn’t yet know if she’ll be involved in the upcoming sequel or tour (“It would be fun, though”). In the meantime, she’s working on an album, “figuring out what my own pop sound is”, and writing for other artists.Performing with Andrea Bocelli at the opening of the FIFA World Cup.Luke HalesIn November, she’ll marry her fiancé, Sam Kim, a former music producer she met in 2017 during a songwriting session. He now works in coding and is quietly here with her on set, ever the supportive boyfriend. They live in Brooklyn.“We got this wedding date really last minute and it’s only a couple of months away, so we need to chop-chop. I don’t know who’s doing my dress and apparently it takes a year to make a wedding dress, so [Dior’s] Jonathan Anderson is out. He has collections to work on; he is a busy man!”Have there been any downsides to her life-changing year? “The only thing is that I can’t go to onsens [hot springs] any more because you’re fully naked going in.” She shakes her head. “It’s still crazy to me. I was a nobody and suddenly I’m a something.”The Times, UKGet the best of Sunday Life magazine delivered to your inbox every Sunday morning. Sign up for our newsletter.