In 1980s Chicago, the wealthy young wanderer Vladimir returns to the city after two years to reunite with his circle of friends, including a young man named Hugh, an art director. Vladimir finds Hugh in a troubling state. For a long time, Hugh has been haunted by a recurring, vivid dream of a grand Victorian house he has never seen in his waking life. What disturbs Vladimir more is that while Hugh dreams, his breathing and heartbeat nearly stop, placing him in a deathlike state. Hugh's dream, once just a silent exploration of the mansion, changes when he encounters a young girl of about thirteen or fourteen with a wise, knowing demeanor among the rose bushes on the property. She calls him ghost, and she has been waiting for him. Her name is Liddell.

The story follows Hugh, Vladimir, and their friend Vi, a former actress and designer's assistant, as they attempt to solve the mystery of the dream. Convinced Liddell is real, Hugh begins a search for the mansion, finding a photograph of a girl who looks exactly like Liddell in an antique shop. As Hugh becomes more enthralled by the dream, Vladimir and Vi become increasingly fearful that he is disappearing from reality. Their investigation leads them to a discovery that defies logic: the Victorian mansion exists, and the current owner has been expecting them for generations, as his ancestors knew Hugh would come. The narrative reveals that Liddell is not a ghost in the traditional sense, but a girl living in a different, adjacent time. To her, Hugh and Vladimir are the phantoms who drift through her home. The central conflict emerges from this temporal paradox as Hugh seeks to bridge the gap between his world and Liddell's.

The narrative is framed through the perspective of Vladimir, a descendant of Russian refugees who has no homeland and carries a deep sense of metaphysical loneliness. While Hugh pursues connection across time, Vladimir acts as the anchor to reality, struggling with the impending loss of his closest soulmate. A key arc involves the group traveling to locate the mansion, only for Hugh to eventually vanish from the physical world. The ending is quiet and ambiguous, suggesting Hugh has successfully crossed over to live permanently in Liddell's dimension, leaving Vladimir to continue his eternal search for home and belonging.

Throughout the story, the characters encounter a supporting cast including a mysterious Japanese woman named Hazuki and the eccentric John Peter Tooy, who view Hugh as a figure pushing the limits of human consciousness. The series explores deep philosophical themes about the nature of home, the fluid boundary between dreams and reality, and the concept of eternal loneliness. Known for its slow-paced, literary, and atmospheric storytelling, the manga is a philosophical mystery rather than a conventional romance, famously serving as the final work of its author before she retired from the industry.