The "Seven Mysteries" of the Strawberry Dorms are mentioned. Nagisa and Tamao start to investigate the first mystery, "The Girl of the Hallway," despite Nagisa's terrible fear of the supernatural.

The month-long summer break has started, and most of the students residing in the Strawberry Dorms are going home. This leaves Nagisa, Shizuma and a few others left behind. Without the interference of other students, Shizuma makes her move on Nagisa.

A final message from Kaori forces Shizuma to reconsider her life's choices, as well as her behavior towards other people.

Nagisa tries to find a club she would like to join, but she's not interested in any of them. Later, she discovers the Étoile's private greenhouse and helps out with the flowers and their delivery to the school events.

Nagisa and most of her friends enjoy a short trip to the beach during "summer school." While there, the girls find their own ways of having fun with each other, and they even get to participate in a test of courage later on. Meanwhile, Nagisa is just starting to discover just how much she misses Shizuma.

Nagisa offers her favorite umbrella to Kagome but does not give her name. Later, Kagome gets help from Chikaru and her friends, and they start to try and find out who the anonymous gifter is. Meanwhile, Tamao tries desperately to fulfill her fantasy of walking under an umbrella together with Nagisa.

Miyuki recounts for Nagisa the events of the past few years, filling in details of the relationship between Shizuma and the now-deceased Kaori, whom they have both grieved for, over the past three years. As she tells her story, she discusses the impact that Kaori's passing has had on the two of them, and reflects, as well, on the effect that Nagisa's arrival has also had on them.

The circle of friendship is broadened, as select first-years attending Miator become room-cleaners/maids for the older students. One such student, Chiyo, becomes the room-temp for Nagisa and Tamao.

Nagisa is shown around the Strawberry Dorms by Tamao, and is surprised by Shizuma's advances again and again. She also finds herself unable to move whenever Shizuma gazes at her. Nagisa discovers that the Student Council feels that Shizuma is shirking her responsibilities, and resolves to remedy the situation. After much searching, she finds Shizuma and convinces her to step up.

Amane awakens after her accident, but has suffered partial memory loss-and among the lost memories is her relationship with Hikari, which leaves Hikari heartbroken. In the meantime, Nagisa and Tamao enter training for the Étoile election and get an unexpected tutor: Shizuma.