Toshiyuki Toyonaga

One summer day a group of sixth-grade boys have an argument about whether fireworks are round or flat when viewed from different angles and embark on a journey for the answer during the annual firework festival. Meanwhile, one of their classmates, Nazuna, is troubled by her parents' separation and decides to choose one of the boys - Norimichi or Yuusuke ...

Shouya Ishida starts bullying the new girl in class, Shouko Nishimiya, because she is deaf. But as the teasing continues, the rest of the class starts to turn on Shouya for his lack of compassion. When they leave elementary school, Shouko and Shouya do not speak to each other again... until an older, wiser Shouya, tormented by his past behaviour, ...