Ichijou Hotaru is enjoying life with her classmates at her new school. In particular, she has come to think of the diminutive Koshigaya Komari, at less than 140cm, as her “cute Senpai.” This feeling soon grows into absolute adoration. Then, one day, Komari calls Hotaru and invites her to hang out together…

Hotaru and Renge are invited to the Koshigaya’s house for breakfast. Afterwards, the girls, accompanied by Kazuha, go to the beach, where Komari’s height leads her to be mistaken for a lost child. On their way home, the girls stop at a railside noodle restaurant, where a prank by Natsumi on Komari backfires due to Renge’s innocence. They manage to catch the last train home on time, but accidentally leave Kazuha behind.

Since the school doesn’t hold cultural festivals, Natsumi suggests they hold their own and invite the alumni, including Kaede, Konomi and Hikage. At the festival, the girls run a café, hold an art exhibit and put on a play. However, they’re play ends up being overwhelming and they end up slacking on food orders. They do eventually work together to prepare some food and have fun. Afterwards, Komari and Konomi help clean Natsumi’s room, where they find a lot of old toys.