When wondering about which club to join, Yako gets a bit agitated when her mother is brought up. Whilst changing, Nayu spots Yako with a bra her mother brought, who gets riled up when Nayu tells her it is too soon for her to wear one. She tries it on anyway and it ends up shifting during PE. Embarrassed, Yako vows never to wear a bra again. Nayu, with the help of her step-brother Keigo, makes a no-cup for Yako, but she declines it. She reveals she is embarrassed to wear a bra over her flat chest since it might cause others to laugh at her. When Nayu explains to her about her breasts swelling, she finally convinces Yako to wear the bra, which she finds more comfortable. Whilst discussing what she went through to make it, the idea of an underwear club springs to Nayu's mind.
Minori Chihara
Nayu Hayama
Sayuri Yahagi
Haruka Shiraishi
Minako Kotobuki
Yako Jingūji
Takahiro Sakurai
Keigo Hayama
Yoko Hikasa
Kiyono Amahara
Yuudai Sato
Hiroki Komachi
Sayaka Ohara
Tamaki Mizuno
Ako Mayama
Tsukamoto-sensei
Gara Takashima
Yōko Sagisawa
Tanuki Sugino
Principal
Katsuhisa Houki
Ōkuma-sensei
Motoki Takagi
Kōta
Naoko Sugiura
Kaori Seto
Takashi Onozuka
Komachi's older brother
Toshiyuki Morikawa
Tsuzuki
Umeka Shouji
Chigusa
Yuichi Nakamura
Tanihara-sensei
Yuiko Tatsumi
Suzuki
