Koi suru nichiyobi watashi. Koishita

Nagisa, a high school girl who has been given three months to live. Without telling her widowed father where she is going, she sets out from the city to the small town where she was born. She recalls her childhood memories, and her love for Satoshi begins to grow stronger. However, she is shocked to discover that Satoshi is having an affair with Eriko, a married woman.