Eight-year-old Hirata Runa, known as Luna-chan, has died after myocarditis linked to influenza, her agency in Nagoya said. Her death came five days after she performed at a concert, drawing attention to the sudden loss of a young trainee and performer.

Runa appeared at DIANNA Project’s Regular Live Vol.70 on 20 September and later posted a message thanking fans and saying she had enjoyed the event. Her agency said she died at about 4am on Friday; no further medical details were released, and her wake and funeral were attended by close relatives. Her family asked fans to remember her as an “eternal idol”, while fellow trainee Miyata Ryoka said she would pause her social media activity to mourn.