I (Takumi Kitamura) am a high school student. I happen to find a diary by my classmate Sakura Yamauchi (Minami Hamabe) that reveals she is suffering from a pancreatic disease. I spent time with Sakura, but she dies.
12 years later, due to Sakura’s words, I (Shun Oguri) am now a high school teacher at the same school where I graduated from. While I talk with my student, I remember several months I spent with Sakura. Meanwhile, Kyoko (Keiko Kitagawa), who was Sakura’s friend, is soon to marry. Kyoko also recalls the days she spent with me and Sakura.