Watch Over the Sky (Kimi wa kanata)

Mio has feelings for her childhood friend Arata, but can't convey her feelings. One day, as they continue their delicate relationship, the two fight over something trivial. After letting tensions settle, Mio goes to make up with him in the pouring rain. While on her way, she gets into a traffic accident. When she regains consciousness, a mysterious and unfamiliar world appears before her eyes.