Anne Nozaki, also known as Juliet, is the main heir to the vast Nozaki fortune. She lives confined within the sprawling family mansion under the strict control of her older brother, Naruto Nozaki, who justifies her isolation with security concerns. This imprisonment severely restricts her social life and any experience of the world beyond the estate.

A critical family secret reveals that Anne and Naruto are not biologically related, a truth Naruto only discovered after his own death, adding tension to their relationship. At sixteen, Anne begins to rebel against her confinement. Her first act of defiance involves secretly obtaining and hiding a kitten within the mansion, deliberately challenging Naruto's known dislike of cats. Her rebellion escalates when she seizes an opportunity to escape by hiding in a delivery truck, successfully fleeing the grounds.

Naruto locates her after her escape. During their confrontation, he acknowledges the unsustainability of her isolation and agrees to grant her greater freedom and a normal life. However, this agreement is abruptly shattered by a violent robbery that results in the deaths of both siblings. In the afterlife, their parents' spirits communicate with them separately. Anne is told it is not her time to die, leading to her return to life. Naruto learns Anne is not his biological sister, transforming his existing feelings into a romantic obsession. This revelation drives his spirit to possess the body of Anne's recently deceased cat.

After surviving the robbery, Anne manifests an ability to communicate with the spirits of dead animals. She later becomes involved with a veterinary practice, where her sensitivity to animal spirits becomes a constant part of her existence. The reincarnated Naruto, now inhabiting the cat's body, maintains his obsessive fixation on Anne. He frequently watches her and exhibits jealousy, creating a complex dynamic where Anne interacts with the cat unaware it embodies her brother's spirit and his enduring obsession.