In this visual novel, you take the role of Amagi, a girl attending a monster high school. As you walk to school on your first day you suddenly lose consciousness and find yourself in a cell with a strange woman claiming to be a detective and saying that you were involved in a murder at the school.
As you talk more with the mysterious woman, you start to remember your week. Using your perception and memory you pinpoint who the most likely culprit is and bring the real criminal to justice.