Rei works part-time at a patisserie with apple pies being her forte. Her love and zeal for her work gains the manager's respect and the latter recommends her for a promotion to a full-time employee. In the process of getting all the relevant documents ready for processing at the company's headquarters, she discovers to her shock, that her name is not on the family registry.
Rei collapses under the shock of discovering that without her name in the family registry, she is technically a nonentity. She desperately asks the help of the staff at the City Office, especially Kiyama, who has taken a keen interest in her case and is thinking of ways to help her. Meanwhile, an elderly man comes to the patisserie where Rei works and seems to have taken an interest in her. Rei's mom, Yoko, finally agrees to meet Rei at the City Office to get her registered.
Rei and the staff at the City Office wait in vain for Rei's mom, Yoko, to arrive. Rei's numerous call to Yoko's phone goes unanswered. After returning home, a newscaster on the television announces the discovery of the body of a woman. This frightens Rei and she tries to phone Yoko again, which was answered by a police officer who informs her that Yoko's phone was left on a bus. However, Yoko herself is nowhere to be found. Later, Kiyama gets a call from Yoko.
The city's free paper, City Watcher visits Patisserie Charlotte to interview Rei and Igawa. The paper features Rei's story with her mom, causing her apple pie to surge in popularity. Kusano Kota comes to the store as promised to try the apple pie made by Ms. Apple Pie. Mao learns the truth of her family, while Natsume tries to fix things with his granddaughters. In the end, Yoko returns with the required documents for Rei's family registry.
Rei is finally able to proceed with her registry after her mom's return. She was asked by her manager to create a unique product as the following month's recommended product. She decides on making tiramisu after Kiyama told her about it. Rei gains the inspiration to improve her tiramisu after receiving an apple-shaped glass charm from a mysterious man.
After Rei sees how traumatised her mom was when she saw Ayukawa, she decides to go to trial. She soon realizes how much money is needed for the lawyer fee. Yoko opposes her daughter's decision to go to trial and refuses to give her any financial help. Hopelessly, Rei seeks financial help from her grandma, Kaori. Kaori relays the message to a concerned individual who decides to help Rei.
Ayukawa pays a visit to Rei's house to tell her that he is her dad. Yoko whilst trying to stop Ayukawa from spilling the truth has stabbed her dad. All of the family members are brought to the police station for investigation purposes. Rei is asked to leave work earlier the next day due to the rumor. Her life starts to get affected by the rumor. Yoko finally tells Rei the truth behind her birth and Rei decides to conduct a DNA test to ascertain her relationship with Ayukawa.
Ayukawa is diagnosed with cancer. Rei finally gets to go back to work. Nakatsu writes an article about Rei that has deeply affected Rei's life. Meanwhile, Yoko is asked to resign from the hospital due to the stabbing incident. Rei agrees to her grandpa's suggestion and decides to move to another city in order to protect her family.
Ayukawa agrees to go to Tokyo to meet Rei for the DNA test, but fails to show up. While Rei is packing for the move, she receives a birthday cake order from Patisserie Charlotte. She accepts it as her final job at the store. The mysterious customer asks Rei to deliver the cake, but things turn out to be another nightmare for Rei.
After the unpleasant birthday party at Kataoka’s, the relationship between Kiyama and Asami takes a turn. Ayukawa finally shows up, but is in poor health. Rei becomes unsure about having the DNA test done. After meeting up with Kusano, Rei gathers up her courage to proceed with the DNA test. And the truth about her birth is…
Rei breaks down after finding out Ayukawa is her biological dad. It not only makes her doubt who she is as a person, but also what she is to her family. With mixed feelings, Rei finally gets her family registry. But time is running out for Ayukawa. Will Rei find the courage to face him before it is too late?