Konna Mirai wa Kiite Nai!!

A high school sophomore, Kayo Hanazono, keeps her affection for her childhood friend Shinnosuke a secret, believing she can avoid consequences. However, her 30-year-old self suddenly appears from the future, warning that Shinnosuke will marry another woman while Kayo remains unmarried. Determined to alter this outcome, the two versions of Kayo work together to ensure Shinnosuke ends up with her instead.