In the final years of Japan's Taisho era, a translator named Fuji moves into the elegantly appointed Kaika Apartment, a luxurious housing complex styled after Spanish Mission architecture. The building is described as having refined single rooms each equipped with a telephone, a ground floor with a public dining hall, banquet hall, and social room, and a basement with an automobile garage and barber shop. Its residents are instructed to embrace progressive living free from old-fashioned habits, but beneath this polished surface, every tenant harbors a concealed past. Fuji's new neighbors include a woman rumored to have poisoned her husband, a middle-aged detective and his much younger assistant who operate as an unlikely pair, and two married couples whose close relationship feels strangely artificial. As Fuji settles in, it becomes clear that he too is keeping a hidden history: he was once the apprentice of the celebrated writer Rintarou Kishima. When Kishima fell in love with a novel Fuji wrote and published it under his own name, Fuji silently continued producing work that appeared under Kishima's name, even after his mentor succumbed to guilt and physical decline and died. Fuji has never revealed the truth and continues to write as Kishima, claiming to have inherited his final manuscripts. Throughout the ongoing series, the narrative follows Fuji as he interacts with a rotating cast of residents, each whose personal mystery unfolds in interlocking episodes. These include Shizuko, a telephone exchange operator with a voice said to bewitch listeners; Kasane, a young woman whose twin sister died in a railway accident years earlier; and the editor Orikasa, who becomes suspicious of Fuji's connection to Kishima's posthumous work. Meanwhile, the young detective assistant Makoto investigates a ghost said to appear on a nearby bridge, a case that draws in a student named Haruo who has been sneaking out at night claiming to await a white ghost. The stories are self-contained vignettes that gradually weave together, revealing the complicated, often eerie human entanglements within the apartment walls. The series is published in Harta magazine and collected into volumes by Kadokawa, with three volumes released as of 2024.