Masajiro Miyazawa owns and runs a pawn shop for generations. His first son is Kenji and his daughter is Toshi Miyazawa. Kenji is supposed to take over the pawn shop as the first son, but he refuses. Masajiro is soft on his son. Meanwhile, Toshi is smart and wise. She gives advice to her father and her older brother. One day, Toshi gets sick.

Six complete strangers with widely varying personalities are involuntarily placed in an endless maze of interlocking cube-shaped rooms containing deadly traps.

Days before graduation, an unassuming teacher takes his class hostage: he's determined to confront the truth about their classmate who died by suicide.

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 - to run away with depending on who wins a race at the pool.