When Aihara Ame was a high school student in Nagasaki, she wasn't confident in herself due to her past. Asano Taiyo was a student attending the same school as Aihara Ame. He was the only person who talked to her brightly. With him, she was able to see her life positively for the first time in her life. She had feelings for him. After her graduation, she went to Tokyo to fulfill her dream of becoming a patissier without telling Asano Taiyo about her feelings for him.
After 8 years, she returns to Nagasaki. One day, she meets Asano Taiyo, whom she has never forgotten, and is elated to see him again. An accident soon occurs, and Aihara Ame falls into deep despair. A man appears in front of her and introduces himself as a guide from the afterlife. He tells her that if she gives her heart to him, he will make a miracle for her.
Meanwhile, Asano Taiyo is a bright person. His family has operated a fireworks shop for generations in Nagasaki. His dream is to become a fireworks expert and succeed his father in their family business. Even though he is a bright and honest person, he didn't tell Aihara Ame about his feelings for her when they were together. He meets Aihara Ame, whom he has never forgotten, again for the first time in 8 years.