Mize Takahashi is a 28-year-old office worker who lives by herself. She's currently dating Sakurai-senpai from the same company―or so she thought. Is it possible that she's actually the one he's cheating on his girlfriend with?! While heartbroken, Mize has an unexpected reunion at her family's restaurant with her childhood friend Ritsu, who is nine years her junior. It has been ages since Mize last saw him, but the person he likes is…actually her?! At age 28, an uncertain love begins.