On her way home from school, schoolgirl Momoko feels a sudden urge to urinate and rushes into a portable toilet in a park. There, she is startled by a homeless-looking man who suddenly speaks to her, causing her to panic and flee. She trips, hits her head hard, and loses consciousness. When she wakes up, she finds herself in a strange hospital with no memory of how she got there, undergoing bizarre medical examinations. It's unclear whether the person being examined is really her or someone who merely resembles her. She is placed on a delivery bed and subjected to highly lewd procedures—having a fecal extraction rod inserted into her anus, her pubic hair shaved off, and her genitals touched by gloved hands. Confused and disoriented, Momoko gradually becomes aware of the hospital's disturbing nature, yet simultaneously feels drawn into a strangely sensual world. This eerie, seductive atmosphere begins to deeply unsettle and arouse her.