Born in 1994. After working as a reporter for the Mainichi Shimbun, Koyama began freelancing in 2023. She received the 66th JCJ (Japan Congress of Journalists) Award for her book “Kuroi Ame Sosho” (Shueisha Shinsho), which documents the damage caused by the “black rain” that fell after the atomic bombing of Hiroshima. Koyama works and resides in Hiroshima.