Hikada Sana returns to his hometown after 5 years away living in Tokyo. Although there are some changes to the town, most has remained the same. On a detour to his apartments, he notices a girl in a shrine maiden outfit watching him when he visits the shrine. He finds out, the next day at school, that this girl is actually Yatsushiro Nanaka , his old childhood friend whom he gave a bracelet to before he left, that she still wears, even to this day.

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