Tomoya and Nagisa convince Kouko that Fuko would wish for her to get married despite Fuko's condition. They talk to the school's administration after finding out Kouko would like to get married on the school grounds. Kouko informs them that Fuko's condition has gotten worse, and she may not awaken from her coma, while Youhei shares his observation that some students cannot see Fuko and others are beginning to forget her and the presents she gave them.

Tomoya realizes that he met Kotomi as a kid, though only she had remembered. Back then, Tomoya had often visited Kotomi, and was her only friend. Around this time on Kotomi's birthday, her parents left for business reasons, and later that day she finds out they were killed in a plane crash. Kotomi ultimately ended up burning her father's important work before anyone could see it. While Kotomi shuts herself in her house, Tomoya comes over and starts cleaning up the garden which is overgrown with grass and weeds. Nagisa, Kyou and Ryou eventually help out too.

The drama club is finally re-established and Koumura is shared with the choir club. Tomoya's home room teacher goes to Tomoya's house to ask his father about his future, but Tomoya's father says that is something that Tomoya has to decide for himself. Seeing the strained relationship between Tomoya and his father, Nagisa offers to have Tomoya stay over at her house for the time being, which he accepts. After coming home from school, Tomoya finds several small kids in Nagisa's house, and finds out Sanae is instructing them in a cram school. Nagisa confides to Tomoya that she feels she did something really bad to her parents in the past, but she cannot remember what it is, and her parents say that she must be imagining it.

Tomoya and his friends are nearing graduation, and are discussing what they will be doing after they graduate. Kyou wishes to be a kindergarten teacher, Ryou hopes to go to a nursing school, Kotomi wants to study in America, and Youhei aspires to be a model. Tomoya still has not decided on what to do yet. Nagisa's sickness returns, making her unable to go to school and take exams. On the day of graduation, Tomoya returns home to Nagisa who wishes to take a walk with him, while holding hands.

Nagisa becomes increasingly bedridden due to morning sickness. Nagisa wants to give birth at home, so Sanae introduces Yagi, a midwife who is to assist in the delivery. Sanae later tells Tomoya that giving birth will be difficult because of Nagisa's weak physique and may even put Nagisa's life in danger, so they might have to choose abortion. However, Sanae leaves the choice up to Tomoya and Nagisa. Nagisa learns of her mother's worries, but she decides to go through with the birth. Akio takes Tomoya to a meadow and tells him more about the day when Nagisa nearly died. Akio carried Nagisa to the meadow and prayed for her life, and Nagisa miraculously regained consciousness. Akio tells Tomoya that while many painful and difficult things will happen, he and Sanae will always be there for Tomoya and Nagisa since they are family. Nagisa and Tomoya take a walk by the river and decide on the name Ushio for their child.

Ushio's fever does not back down and Tomoya decides to stay home to take care of her. In case he had to leave home, he calls for both Akio and Sanae to take his place. Ushio tells Tomoya that she wants to go on a trip again like last time, but he declines and tells her that it will happen once she gets better. After resigning from his work, Akio offers him some money, but Tomoya declines his kindness and Akio states that every man has something to protect. After several months, winter arrives, and Ushio's fever still does not back down, and Tomoya seems to be getting sick too. Ushio once again ask Tomoya to go on a trip, and he ultimately accepts thinking that he might not be able to fulfill another promised wish. After they leave the house, Ushio's fever worsens, and she dies in his arms right after telling her father that she loves him. Soon after, Tomoya collapses as well.