Tsukimi (Rena Nounen) came to Tokyo to become an illustrator. She is crazy about jellyfish. Tsukimi is not very confident and she hesitates around men or attractive people.
She lives in the communal apartment Amamizu kan where men are not allowed. At the Amamizu kan, only otaku women, who believe men are not needed, live there.
One day Tsukimi gets into trouble at tropical fish shop. At that time, a stylish woman helps Tsukimi, but, in fact, the pretty woman is Kuranosuke (Masaki Suda) a male university student. Kuranosuke dresses like a woman because he was raised at the side of his powerful politician father and he does not want to become a politician.
Kuranosuke becomes interested in Tsukimi and Amamizu kan. He visits her at the apartment and hangs out with her. Tsukimi keeps his secret from her neighbors. Kuranosuke helps Tsukimi improve her appearance and she starts to change.
The story focuses on Tsukimi's social growth after she meets the cross-dressing Kuranosuke and the fight to save Amamizukan from redevelopment. Included is a subplot about the love triangle between Tsukimi, Kuranosuke, and Shuu. It is largely faithful to the manga/anime, with some early scenes compressed together, scenes from the manga added in, and a few movie-only inspirations.
- Rena Nounen as Tsukimi Kurashita
- Masaki Suda as Kuranosuke Koibuchi
- Hiroki Hasegawa as Shuu Koibuchi
- Chizuru Ikewaki as Banba
- Rina Ohta as Mayaya
- Azusa Babazono as Chieko
- Tomoe Shinohara as Jiji
- Katase Nana as Shoko Inari
- Mokomichi Hayami as Yoshio Hanamori
- Sei Hiraizumi as Keiichiro Koibuchi
- Tomoya Nakamura as tropical fish store clerk
- Kenta Uchino as Kashiwagi