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.

In an alternative timeline where Tomoya and Tomoyo are dating, Tomoyo becomes student council president, but bad rumors start around the school due to Tomoya's bad reputation. Tomoyo becomes busy during the school festival, and continues to be so while she attempts to save the sakura trees in town. Tomoya realizes that he is holding Tomoyo back from greater things, and despite both sides being reluctant, they break up. Time passes as Tomoyo's reputation builds and Tomoya and Youhei watch on the side through her many accomplishments, one of them being ultimately saving the sakura trees by the winter. At that time, Tomoya and Tomoyo meet and talk for the first time in months and they decide to become a couple again.

Yohei and Sanae go out on a date, accompanied by Mei, Tomoya and Nagisa. During the date the group witnesses a young girl being bullied by some slightly older boys. The scene is resolved by the girls older brother rushing in to help his sister. Mei remembers how Yohei used to be like that, but once he joined the football club he didn't seem to care about her any more. The group then tries to provoke a brotherly response from Yohei, to get him to stand up for his sister; Tomoya pretends to be romantically interested in Mei, but despite being shocked, Yohei doesn't say anything to oppose them. Mei decides to stay a little while longer, as she can't leave things the way that they are.

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.