Uta Kata

Plot
On the day before the summer holiday, Ichika Tachibana discovers that the charm attached to her cell phone has somehow wound up inside a mirror in the old school building. A girl named Manatsu Kuroki, inside the mirror, offers to return the charm and phone in exchange for a favor. When Ichika accepts, Manatsu emerges from the mirror, but Ichika finds to her chagrin that the charm's stones' have all taken on different colors. Her indignation soon turns to delight as she is transformed by the charm and given an incredibly moving experience in the skies above Kamakura.

After returning to the old classroom, Manatsu asks that Ichika use all the colored stones in the charm and record her experiences and thoughts. Starting with the facade of Manatsu as her text-message pal, Ichika begins to entangle herself in a web of small lies and deceptions.

When Ichika faces various dangers during the summer holiday, she at first uses the Djinn's power within the stones to resolve them supernaturally. But as the summer draws on, she begins to use the power even though there is no imminent danger. Through each experience with the Djinn she learns about the willfulness of herself and others. Slowly, the power of the Djinn erodes her emotional, physical, and mental strength, and she abuses the power to the point of attempting murder.

Meanwhile, Ichika's tutors, Sei and Kai, are tormented by Ichika's ordeal—Sei had gone through the very same thing six years ago. They very much want to prevent Ichika from experiencing the same trials, but are bound to the rules of the ritual; when Sei tried to interfere, he was turned into stone as a penalty. Although Ichika tries to abandon using the Djinn's power altogether, she finds herself losing control over her actions. Faced with fear, sadness, or anger, she finds that the Djinn grant her power against her will. Not only this, she finds that she cannot discard the charm, as it will fly back to her.

Ichika, in fact, had been subjected to a ritual judgment determined from the time she was conceived. Saya, the final Djinn, would take a young person of fourteen years—the age between the innocence of childhood and the hardness of adulthood—and show him or her the world through the eyes of the Djinn. The individual would experience seven trials that contrasted seven virtues and sins: affection and resentment, temperance and hubris, devotion and rebellion, honesty and treachery, reason and envy, passion and lust, wisdom and machination. When Ichika is thus led to despair in humanity and disgust of herself, Saya binds her to the mirror and asks her to decide whether to destroy humanity or herself.

In response, however, Ichika refuses to choose either. Saya declares that as a violation of the rules, and drives her scythe towards Ichika's body. Sei shatters his stone skin and tries to stop the scythe, but Ichika decides that it is better that she die rather than see him hurt. Manatsu, in defiance, drives herself into the scythe, saving Ichika's life. Kai returns the life energy that kept him in human form to Sei, and both he and Manatsu revert to their original forms: shards of the old mirror.

When school resumed in the fall, Ichika decided to remain at Kamakura rather than join her parents in Italy. Elsewhere, Saya determined to move on and judge the next teenager.

OVA: Shotou no Futanatsu
In the OVA Shotou no Futanatsu (初冬の双夏?, Twin Summers of the First Winter), Ichika hears that Manatsu has been seen again, one week before her birthday. Not long after the fall term had begun, Sei had transferred to a German university in an exchange program. On Christmas Eve, both discover that Manatsu and Kai's shards had vanished, and they both reunite with Ichika and Sei, respectively. They had returned for one last night and to say goodbye. After an evening with Ichika and Sei, the shards return to Saya's old mirror during the night. The next spring, Ichika enters a new school year with her friends, while Saya's experiments continue with a new test subject.