After a mysterious accident, Ogi Takumi awakens in a strange hospital where he is treated for mental instability. However, he soon begins experiencing vivid, disturbing sensory hallucinations that seem to be the leaked memories and traumas of others. Guided by a mysterious investigator, Takumi ventures into the hospital's hidden underground, uncovering a nightmare of medical experimentation and suppressed secrets.
Takumi finds himself caught in a web of manipulation and desire as he is seduced by Amano-san, who hopes to use him to uncover the hospital's dark secrets. Amidst a budding, awkward romance with Aoi, Takumi discovers disturbing sexual undercurrents involving the other residents and staff. As he delves deeper into the facility's mysteries, he is plagued by haunting visions that blur the line between reality and illusion.
Midori suffers from vivid, traumatic hallucinations of being forced to replace her mother while undergoing mysterious medical treatments administered by the Director and his staff. As her psyche fractures under the influence of medicine and hypnosis, she is treated more like a specimen than a patient. The horror deepens as the Director reveals his collection of human remains in the underground, viewing the broken girls as mere puzzle pieces.