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Synopsis of the Opening Plot -

The movie starts out in the present (movie takes place in Mika's past) and she telling someone (through her mind) how much pain and joy her meeting this person (Hiro) had brought her.
The movie then goes into telling their story.
Mika and her friend Aya are in the bathroom applying make up, and they go to see Nozomu, a boy Aya has a crush on. When they see him in the hall Nozomu ignores Aya and asks for Mika's phone number instead, Aya cuts in, asking for his and taking away his attention. Mika slips away and bumps into a boy with bleached hair. After saying sorry she runs off, the boy watching her. Aya finds Mika later and is disapointed Nozomu took a liking to Mika. Mika, being a good friend, promises she'll never date Nozomu.

After Mika loses her cellphone one day, she goes to look for it in the library. She hears it ringing and picks it up, saying thank you because she thinks it's her friend Aya calling the phone. Instead she hears a male voice, when she asks who it is the boy replies 'secret' and hangs up. Mika looks through her phone to see all her numbers have been erased and only a number she doesn't know is listed. She calls the boy back and asks why he did that. He replies, "if they want to talk to you, then they'll call you." and asks if his number is listed first. He hangs up again.

The boy continue to calls Mika everyday. She wonders why he does it, and he refuses to tell her who he is. The boy asks Mika alot about herself, and they seem to be able to talk very easily. During a fireworks fesitival, the boy vaguely describes how he looks and Mika fails in drawing him.
Mika begins to question the boy, and to prove he's near her, he says to look in the sky and take a picture of a jet passing through the sky. He tells her it's their first memory/moment together.

A day after Mika's birthday, the boy wants to celebrate with her, and tells her to meet him by the pool. Scared and excited, Mika decides to go. After Aya applies makeup on her, Mika heads to the pool. She waits for him, and just as she decides he's not going to show, he appears and hands her flowers. Mika notices his hair and isn't convinced. To prove he's the same boy who talked to her on the phone. He shows her the photo of the jet plane in the sky. Mika calls the flowers pitiful and runs away.
Aya later asks how it went. Mika replies that the guy was a scary silver haired boy.

While on her way home, Mika follows Hiro and sees him planting the flowers. He sees her and sprays a hose into the air, creating a rainbow. He tells her it's her real present, and they both laugh. Mika notes how easy it was for Hiro to win over her heart every time.