Chiyoda High School

Lore & Background

Chiyoda High School is where the central relationship of the series unfolds. It is here that Aya Osawa, an extroverted gyaru with a passion for rock music, interacts daily with her aloof classmate Mitsuki Koga, unaware that Mitsuki is the same person as the masked record store clerk she has a crush on, whom she calls "Onii-san." The school setting is crucial for the series' dramatic irony, as Aya confides in her friends Chizuru and Mao about her feelings for Onii-san, all while Mitsuki sits nearby, listening. It is also where Megumu Narita, a friend and classmate, becomes the first person to deduce that Mitsuki and Onii-san are the same person, after noticing their similarities. The school provides the mundane, everyday environment where the two girls navigate their friendship, with Mitsuki taking measures to prevent Aya from figuring out her secret identity. Ultimately, it is within this setting that their connection deepens, leading them to begin dating.

Reader's Guide

Chiyoda High School is the central civilian setting for the series, serving as the stage for the daily lives of Aya Osawa and Mitsuki Koga. It is where they attend class as classmates, interact with their mutual friends, and where the central dramatic irony of the plot plays out. Aya, unaware that her crush Onii-san is actually Mitsuki, frequently discusses her feelings with her friends Chizuru and Mao within the school's halls. This forces Mitsuki to constantly maintain her aloof facade to avoid revealing her double life. The school is also where Megumu Narita, a perceptive friend, first connects the dots between Mitsuki and the record store clerk, becoming a key supporter of their relationship. For fans, Chiyoda High represents the normal, everyday world that contrasts with the secret world of the record store. It is the place where Aya and Mitsuki's friendship is tested and ultimately deepens, providing the foundation for their romance to blossom away from the prying eyes of the store's other customers.

Did You Know?

• Mitsuki Koga wears a facemask and androgynous clothing while working at the record store to maintain her anonymity, leading to her being mistaken for a guy.
• Future Diary (Mirai Nikki) was originally a manga by Sakae Esuno, serialized from 2006 to 2010, and has no known connection to a Twitter story by Sumiko Arai in 2021.
• Chapters of the manga are limited to four pages because Twitter only allows four images per Tweet.