Kuroshi Mayama, age 14, lives alone with his mother Namiko. Though he was just under the age of one when he came to this town with his mom, he remembers everything from that day: Gettings on the bus in his mom's arms, an old woman who spoke some words to him, and the encounter with a poet... One night, with Kuroshi's birthday approaching, Father shows up unexpectedly. He insists that he and Kuroshi's mother had made an arrangement – that Kuroshi was to live with his mother until his 15th birthday and then live with his father. As Kuroshi's world gets turned upside down, his family, the people around him and even himself start to change.