Tsutomu and Mikako have tea at Mikako's father's apartment. He has a white kitten named Shiro. Mikako learns that her father has been constantly sending her letters since the divorce, but Ruriko has intercepted them and thrown them all away. Her father says he still loves her and her mother. Ruriko confesses her insecurity about Mikako to Toku-chan. Mikako, angry that her mother deceived her, avoids her. She still hasn't seen her mother by the time she comes home from school the next day, but when she goes to the bathroom, she finds her mother passed out on the floor, having vomited blood. Mikako panics, but Tsutomu comes to her rescue.
At the hospital, Ruriko is diagnosed with a gastric ulcer, much to everyone's relief. Tsutomu telephones Mikako's father and asks him to show some support. Mikako's father visits Ruriko in the hospital and asks her to give their relationship another try.
Meanwhile, Ayumi engineers a reconciliation between Yuusuke and Body-ko.
On the last day of school, everyone shows up in fancy dress. Mikako, Risa, and Pi-chan (forcibly) give Ayumi a makeover.
Mikako spends the summer having fun. At a sushi restaurant with her father, she learns that her parents are going on a hot-springs trip together. Mikako is shocked--her mother had lied and told her she was going on the trip with another comic-book-artist friend.
Tsutomu accidentally grabs her chest while they're swimming together. He says it's all right, her chest doesn't feel any different from her back.
Mikako and Tsutomu run into Risa and Takeshi at the local festival. While Mikako and Risa go off to the bathroom together, Takeshi tells a nervous Tsutomu that he's glad Risa has such good friends, because he's hardly ever at home.
Akindo goes to the Nakasu's summer home in Karuizawa for a training camp. It turns out to be a huge, palatial mansion with a tennis court, a swimming pool, and a French cook. The others have fun playing in the pool together, but Body-ko is upset because nobody will play tennis with her. She's fighting with Yuusuke, who is trying to get her to join them, when Shuu-chan shows up. His family's summer home is next door to hers, too. Body-ko leaves with him, brushing off Yuusuke. Ayumi is troubled to see all this.
There's a storm warning on TV.
Mikako, Risa, Pi-chan, and Ayumi take a bath together and become better friends. The other three drag the secret that she likes Yuusuke out of her, and Ayumi starts to cry.
Meanwhile, the boys are playing cards. Tsutomu, standing at the window, sees Body-ko running outside.
Meanwhile, the boys are playing cards.
Ayumi calms down and the girls drink tea together. Mikako, standing at the window, sees Body-ko running outside.
Body-ko goes to Shuu-chan's house, where she left her contact lens case. She learns that his girlfriend dumped him, and confesses that she's still loved him all along. He has loved her, too, but Body-ko admits that she's dating somebody right now. She says she doesn't mind if Shuu-chan kisses her, but he's disgusted that she could be so unfaithful to her current boyfriend.
Meanwhile, the others have noticed that Body-ko is missing. She comes back just as Yuusuke is about to go out looking for her. Upset, she runs to her room, but Yuusuke follows her. He says, "I just have one question. Answer me truthfully. Did you go to see him?" She doesn't answer, just keeps crying. Yuusuke says, "All right, I understand. Enough already. It's over." Body-ko cries "No!" as he storms out, surprising the others eavesdropping outside. They're torn between trying to comfort Body-ko and calm down Yuusuke. Tsutomu tries to stop Yuusuke, but it's Ayumi who dashes past and follows him out the door.
Ayumi chases after Yuusuke, trying to stop him, but he ignores her until she stumbles and falls. By that time, though, they're lost in the woods. It starts to rain, and they find shelter in a cave. Yuusuke is amused by her candid reactions to his teasing. When he's with Body-ko, they just fight all the time.
Mikako and Tsutomu have a midnight snack together in one of the bedrooms. Tsutomu suddenly tries to make a romantic move on her, and Mikako screams bloody murder, drawing Risa to the rescue. Risa feels sorry for Tsutomu as Mikako snuggles up to her in bed, and Tsutomu lies awake and wonders if Mikako really loves him after all.
Yuusuke is shocked when Ayumi offers her lap as a pillow, but realizing she's only trying to be kind, takes her up on it.
In the morning, Pi-chan wakes up and finds Body-ko gone, with just a note of apology. Yuusuke and Ayumi return safely to the house, in need of a bath, a meal, and some bandages. They're having fun together until Shintarou brings the telephone to Yuusuke. He packs up and returns to Tokyo to check on Body-ko.
Mikako invites Tsutomu to go for a walk with her, but he brushes her off. Risa explains that Mikako has to communicate her feelings to Tsutomu, and that someday, she won't mind it when he does that.
At her apartment, Body-ko tells Yuusuke she won't fool around or be selfish anymore, so please, don't tell her it's over. They kiss.
Ayumi falls asleep by the pool and dreams happily of her night with Yuusuke.