With the episode "Secret," Strawberry Panic begins its long glide to its conclusion. Two new elements are introduced into the narrative: the Etoile election gets underway, and Nagisa investigates what happened to Shizuma’s Etoile partner. As we shall see, the discovery of Shizuma’s secret past will explain the previous failures Nagisa and Shizuma have had in advancing their relationship, and the Etoile election will set the stage for a dramatic conclusion to their romance.
The episode brings up several times the idea that Shizuma has "changed." Tamao tells Nagisa about the lost Etoile, that she "passed away, "and that "[e]ver since that day, Shizuma-sama changed." The anime then jump cuts to Miyuki telling Shizuma, "Shizuma, you’ve changed. You actually take your job as Etoile seriously," followed by Miyuki thinking to herself in the bath, "You’ve changed, Shizuma." We have a concensus of observers who agree that Shizuma has been changed one way, by the death of her friend, and then another way, by the appearance of Nagisa.
The metaphor Miyuki uses to explain Shizuma’s change are winter ones: ice, and its melting; the seasons, winter turning into spring: "You’ve changed. You used to be like an iceberg; no one can touch your heart. Just like an iceberg, you were always cold and removed. Then this iceberg began to melt. Your heart is ready to welcome spring. That girl may be the one to bring you this spring." Nagisa thus brings a restoration, the frozen heart brought back to what it had been before, and the seasons turning around to a new spring, life to what it had been before the winter. Miyuki imagines for Shizuma a reverdie: having been made into a death by Kaori’s death, now Shizuma will be made into spring by Nagisa’s new presence.
In the deepest sense, what Miyuki says is true. We know that from the series’ conclusion, where Nagisa and Shizuma consummate their love. But it is not simply true, since as we see in the following episode, the dead Etoile retains Shizuma’s heart in ice, and in fact Nagisa has not melted it entirely. So the real question to ask is "has Shizuma really changed? has Nagisa changed Shizuma at all?"
Perhaps not. Perhaps the truth is the other way around, that it is Shizuma who has changed Nagisa. In fact, I think we can even say that Shizuma has transformed Nagisa into a second Kaori. The proof-text for this assertion is the extraordinary moment in which Shizuma encounters Nagisa playing the piano at night. Let me set the scene. Nagisa is troubled, thinking about the lost Etoile and her relationship with Shizuma, and, unable to sleep, is playing the piece she and Shizuma had played together. Shizuma is awake, apparently looking for the key to her vacation house, wandering in the dorm halls, and overhears the piano music. Nagisa is caught up in her memories of Shizuma, when they first met, their first kiss. "I…and Shizuma-sama…" Shizuma stands stock-still at the door, watching Nagisa play unawares. What does Shizuma see? Even though the time is night, and the room is dark, unlit, what she sees is almost whited out in light. It appears to be Kaori and not Nagisa, since there is a bow in the girl’s hair that Nagisa does not wear. To make this point unmistakable, Shizuma gasps. For this moment, Nagisa is Kaori.
What is going on is this. Part of the way Shizuma has allowed Nagisa to become close to her is by unconsciously engaging Nagisa in actions and in places that repeat Shizuma’s own history with Kaori. This pattern will become much more evident in the subsequent episode in which Miyuki tells Nagisa about Kaori: we will see there that the tree where Shizuma meets Nagisa is also the place she and Kaori first made love; that Kaori loved the greenhouse, so that when Nagisa gardens there with Shizuma, she is filling Kaori’s place. We learn in the current episode that Kaori loved the piano music Nagisa is playing; in teaching her to play it, Shizuma sets Nagisa up as a reminder of Kaori. Even Shizuma’s plan to take Nagisa to her vacation house repeats the earlier time when Shizuma, Miyuki, and Kaori had gone there together. We have already talked about how Nagisa acts as Etoile with Shizuma; but that is another way of making the point we are making here: in a substantial part of her relationship with Shizuma, Nagisa has been standing in for Kaori. The fact that at crucial moments in her relationship with Nagisa Shizuma is overwhelmed by the memory of Kaori reflects not just the remnant of Kaori in her heart but the extent to which Nagisa herself is acting like Kaori.
From this perspective, far from releasing Shizuma from what Miyuki calls "the shackles of the past," Nagisa is binding Shizuma in them. Rather than changing Shizuma, Nagisa is perpetuating the impossible wish that Kaori never died. It is no wonder Nagisa and Shizuma’s relationship never gets anywhere. At every moment where Nagisa gets close to Shizuma, she leads Shizuma directly back to her lost love. Shizuma’s world freezes her in her past: everything, Nagisa not excepted, returns her to Kaori, and to the loss of Kaori.
All the same, if we look the more closely, we can see where Nagisa’s individuality does come forward. It is in this episode that she consciously expresses to Tamao and to herself that she is in love with Shizuma. More than that, she explicitly chooses Shizuma over Tamao: with apologies, and with a concern for hurting her friend’s feelings, she nevertheless breaks her date with Tamao to go with Shizuma instead. Finally, it is Nagisa, and not Shizuma, who starts the whole chain of events that leads to the revelation of Shizuma’s past with Kaori. Once Nagisa finds out from Chiyo that Etoiles come in pairs, she forces the question of Shizuma’s partner from Chiyo, to Tamao, and then to Miyuki, who finally brings it to Shizuma. No doubt Nagisa is the younger and the naive partner in her romance with Shizuma, but it is Nagisa who plays the adult role to move her romance with Shizuma forward into actuality. There is a decisive and practical side to Nagisa we should recognize and appreciate.
A final note: I have not talked at all about either the music in Strawberry Panic, or the motif of the moon. There are various musical phrases that are repeated in the anime and no doubt have connotative significance: I am thinking of the passage Nagisa plays at the piano, for example, which we will hear at various times as a significant background music, to tell us something about what we are watching. And the moon really must have an important significance in defining the state of the romance it shines upon. If I have the opportunity, I may watch the series over again just to work out how the music and the moon signify in Strawberry Panic.