Twelve-year-old Ame Sakurai lives in Tokyo with her father Tomoharu, 28, an entomological photographer. Tomoharu has gone off on a trip to Taiwan to photograph insects, and Ame begins to fret and worry when he stops calling. Finally, two weeks after his last contact, Tomoharu abruptly shows up at home. He was pursuing a butterfly in the mountains when he fell into a pit and nearly died, he explains.
When Ame burns herself in the kitchen one day, their neighbor Akiko Koyanagi comes to her aid, and after that Ame, Tomoharu, and Akiko become friends. Ame even fantasizes Tomoharu and Akiko getting married. But then Akiko’s decayed corpse is discovered in the neighboring apartment: betrayed by her fiancé, she had killed herself a month earlier. Ame and her father had befriended Akiko’s ghost. Ame is unsettled to discover that neither her father nor Akiko actually appear in the picture they had taken of the three of them together.
In the midst of these developments, Ame sees her mother Tsukie, 38. Tsukie reveals that Tomoharu is not her real father. Ame is the product of an affair Tsukie had had with a married architect named Nagashima. When she became pregnant, Tsukie decided to raise the child on her own, and told Nagashima they were through. But on that very same day she met Tomoharu, then a middle-school student living in a children’s home after having lost both of his parents at an early age, and they subsequently fell in love. As soon as Tomoharu turned eighteen, they officially got married, but not long after that Tsukie resumed her relationship with Nagashima. She later divorced Tomoharu and married Nagashima when his divorce from his wife was finalized. Now Tsukie wants Ame to come and live with her and Nagashima, but Ame refuses.
Ame has only one close friend among her classmates, but when his parents get divorced, he moves away to Kobe, his mother’s hometown. Ame is fond of a particular tree that grows in an open space between buildings, and wants to give it a name, but then it gets chopped down as construction starts on a new apartment building. “Everybody and everything I look to for support is disappearing,” she laments.
Then Tomoharu’s younger sister calls to tell Ame that his body has been found in a pit in the Taiwan jungle. Ame and Tomoharu’s ghost return to an amusement park they had visited together when she was three. They take a ride on the ferris wheel, and when the gondola reaches the top, Tomoharu tells Ame about the Buddhist teaching that the souls of the dead remain in this world for 49 days after death. This is the 49th day since he died, he says, and then vanishes.
Although cast as a tale of the supernatural, this is first and foremost a story of the love between father and daughter, told in powerful, lyrical prose.