As cultural festival preparations intensify, student council leaders Reiko and Shintaro patrol the campus together, checking on each club's progress. After sampling a drink from another student, Reiko begins to feel strangely unsettled and draws Shintaro into a classroom arranged as a dark maze. Inside, a confusing mix-up leaves her disoriented, and Shintaro later notices her distracted manner. Concerned, he turns to fellow council member Misaki for advice, leading the three to plan an amusement park visit that takes an unexpected turn when Misaki disappears and Reiko receives a startling message.