In this slow-burn romantic manga, a high-schooler saves a girl on the train from a molester, and he gets close to her…but this girl is secretly 12 years older than him! A high school boy, Kaoru Momota, saved a high school girl named Hime Orihara as she was getting molested on the train one day. The two of them fell in love with each other, but she has a secret that she can't tell anyone. "I'm...actually 27 years old." The high school girl actually turned out to be a 27-year-old woman! What challenges will they face together with such an age gap?!