After graduating from high school, most students say goodbye to academia and move on with their lives. However, Hana Natori, now 25, finds herself back in the student role. Her aunt asked her to take over for her cousin Kaho Miyoshi, who refused to attend school. Since they resemble each other, Hana agreed to be the perfect substitute. But when an old high school classmate, now a teacher, Okito Kanie recognizes her, she worries he will reveal her secret. Instead, Kanie surprises her with a kiss and unexpected intentions.