On August 18, 2023, Emperor Naruhito, Empress Masako and Princess Aiko attended a viola concert at Suntory Hall in Tokyo that was given on the occasion of world-famous violist Nobuko Imai's 80th birthday. Nobuko is a Japanese classical violist who had an extensive career as soloist and chamber musician. She is currently a member of the Mito Chamber Orchestra, a professor at the Geneva Conservatory, and performs around the world.