A young boy named Daigo lives with his mute half-sister, Kiriko, and is haunted by the death of his mother. Daigo, previously a carefree and spirited child, becomes increasingly withdrawn. When he discovers an injured rabbit at their school, he mercilessly puts it out of its misery, leading to a disturbing sequence of events that unravel his already fragile psyche. Afterward, Daigo and Kiriko visit a nearby amusement park, where Daigo wins a peculiar plush rabbit. This seemingly innocuous toy begins to manifest itself in horrifying and surreal ways, plunging the siblings further into a nightmarish reality.

Kiriko, an illustrator of children’s books, starts noticing unsettling parallels between her illustrations and the bizarre events surrounding Daigo. As both siblings grapple with their psychological trauma, inexplicable phenomena continue to escalate, weaving a chilling tapestry of dread. The boundaries between reality and imagination blur as they confront their darkest fears, with terrifying consequences. Their strained relationship faces severe trials as they strive to uncover the truth behind the ominous occurrences and their dreams laced with terror.