The manuscript of the new work left by Asami (Saya Yamaguchi) is based on the mass suicide of five female high school students "White Bird Cage Incident" that happened 15 years ago... At that time, Asami (Hina Ire) was still thereChildren's welfare home, she decided to work hard because of this incident and was admitted to high school.She just thought that she didn't need friends, as long as she spent these three years in peace, she walked into the school gate.However, unknowingly, she formed a circle of friends with her classmates Emi (Hirohiro Hirasawa), Kanade (Mikai Hayasaka), Yurika (Mikai Shirai), and Yuki (Riki Kamada).Live a pampered life.
At first glance, the five of them seem to be living a peaceful and ordinary high school life, but in fact everyone has their own troubles... During the summer vacation of their senior year in high school, the five of them, who could not bear the pain, planned to commit suicide together.So, how did the incident end?And today, 15 years later, what is Asami’s intention in rewriting this incident?