Stepping away from the manufactured, smiling tropes of traditional idols, BRATS allowed Rei to channel a raw, punk-rock energy. Serving as the lead vocalist, her deep, powerful voice contrasted sharply with her delicate visual appearance. The band provided a stark departure from her early modelling days, positioning her as a legitimate musician within Tokyo’s underground rock circuit. Global Breakthrough: The Ladybaby Explosion
: In 2014, she was a winner in the Miss iD 2015 competition. This victory served as a bridge to her mainstream popularity and her eventual entry into Ladybaby. The Ladybaby Era (2015–2017)
: Despite the fame, Rei grew dissatisfied with the manufactured idol image. She eventually left the group in November 2017, citing throat issues and a desire to pursue music that felt more authentic to her personality. Transition to Rock: BRATS and REIRIE rei kuromiya junior idol
Kuromiya's career took a pivotal turn in August 2011. At just ten years old, she formed the all-female rock band BRATS (stylized as BR△TS) with her older sister, Aya Kuromiya, on bass, along with Seira Goto (guitar) and Maria (drums). Rei served as the band's vocalist and guitarist. Forming the band with her sister allowed her to move away from the purely visual nature of junior idol work and into a space where she could express herself through music and live performance. In an interview with TuttoRock Magazine , the Kuromiya sisters revealed they formed the band when they were still in elementary school, highlighting their early dedication to musicianship. The band became a long-term outlet for their creative energy and a means to control their musical direction.
: In BRATS, Rei famously requested that fans not wear LADYBABY t-shirts to their shows. She wanted to be seen as a musician, not a "product". Stepping away from the manufactured, smiling tropes of
For Kuromiya, this era was a stepping stone rather than a defining creative period. Unlike many peers who faded into obscurity after the collapse of the junior idol market, Kuromiya possessed a distinct, rebellious charisma and a genuine passion for music that allowed her to pivot completely. The BRATS Formation: A Shift to Rock
The devoted fanbase surrounding Rei Kuromiya is a remarkable aspect of her career. Her fans, affectionately known as "Rei-chan's angels," have been instrumental in supporting her throughout her journey. They eagerly follow her projects, attend her concerts and events, and actively engage with her on social media. Global Breakthrough: The Ladybaby Explosion : In 2014,
In addition to her work with Sakura Gakuin and LOKI, Rei has also pursued solo activities. She has appeared in various Japanese television dramas, such as "Taisetsu na Koto wa Subete Mama ga Oshiete Kureta" (2011) and "Shirato Koubanjo 5" (2012). Rei has also modeled for several Japanese fashion brands and magazines.
The Japanese term "junior idol" (ジュニアアイドル) generally refers to child and teen entertainers, typically between the ages of eight and fifteen, who model and perform in gravure (glamour) photo shoots, music videos, and other media. The industry emerged as a distinct subculture in the 1970s and reached a peak in the mid-2000s. While some view it as a training ground for future stars, it has been heavily criticized by sociologists and child rights advocates for the way it sexualizes minors for an audience that is largely adult men. Activities often involve young girls in swimsuits, school uniforms, or other costumes, striking poses that are framed as "innocent" but are often imbued with suggestive undertones. The public has grown more aware of this issue, and several talent agencies have faced police questioning.
: She made appearances in several television dramas and music videos early in her career. Rise to International Fame: LADYBABY