When Yuki's classmate suddenly dies, rumors begin to spread about her death and the relationships between Yuki and her classmates are disrupted amidst grief and forced normalcy.

The "EXTREME FLASHBACKER" machine can repel annoying people by replaying their traumatic experiences. Kaede makes full use of the machine to deal with nuisance customers at the convenience store where she works. One day, a robber barges into the store suddenly while she is at work.