On the surface, Fujimiya Kaori (voiced by Amamiya Sora) is an ordinary high school girl. However, few people know that a rare disease can only keep Kaori's memory for a week. Once a week is up, all the friends and happy things that once made her feel good will be forgotten. Carrying such pain, Kaori suppressed her feelings, put on a cold mask, and lived a lonely life in isolation. Kaori's weird personality made the cheerful and optimistic boy Hase Yuki (voiced by Yasuo Yama) very curious. He took the initiative to approach Kaori and asked to become friends. After learning about Kaori's condition, Yuki did not retreat. Week after week, he became friends with Kaori again and again with his kindness. As time went on, a solid bond was formed between the two young and kind children.