Every last Thursday of the month at an all-girls high school, the students of Class 2–5 cast their votes in a popularity poll. The results classify them into Grades A, B, C, D, and F. If they fall into Grade F, they become legitimate victims of school violence.

An unassuming father becomes a target when he kills his daughter's abusive boyfriend — who happens to be the son of a cold-blooded crime boss.

A humble office worker's peaceful family life comes to an end after he makes a grave decision for the sake of his family.