The next morning, Sakuta reveals he had not slept all night. At school, he discovers his peers, including Yuma and Tomoe – the girl he had encountered before his "date", have forgotten about Mai. Rio proposes the school's atmosphere and sleeping caused the students to no longer remember her; like Schrödinger's cat, her existence cannot be confirmed by those who refuse to acknowledge her. As such, Sakuta attempts to stay awake as midterm exams approach...