Summer vacation is over, and the Aozora Cultural Festival is approaching. After things went well with Mami at the fireworks display, Honda is delighted to be spending more time with her preparing for their class' attraction. Meanwhile, Mishima checks the shops by the station in order to gather cardboard for his class...

After participating in the three-legged race with Mami, Honda believes they've grown closer. However, when he asks her out on a date, she says... With more opportunities to hang out as a foursome with Mishima and Miharu, Honda is glad to be spending more time with her. When Mami says she wants to thank Honda for helping her train for the three-legged race, Honda suggests a group date with Mishima and Miharu, but Mami's attitude towards Honda is as disinterested as ever...

With the Sports Festival coming up, Mishima and Honda's classmates have high expecetations for them as members of athletic clubs. Honda is made to participate in multiple events by his class. Mami is disgusted by Honda's attitude, but when Honda says something, she ends up signing up for the three-legged race as a co-ed pair with him. The unathletic Mami isn't happy about it, but Honda begins training with her for her sake. As the school continues to gear up for the sports festival, Miharu looks on with a sad expression...

When Honda spots Miharu having a friendly conversation with their classmate Sanagi Nasa in the waiting room of a hospital, he decides to investigate Sanagi's identity and his relationship with Miharu for the sake of his best friend Mishima. Meanwhile, Mishima gets caught in the crossfire of an argument between the track and field team and has been called to the student council room, where he is standing before third-year and student council president Nakajima Mikado and his friend Sakurakoji Masamnue alongside second-year Asumi Natsu.

Disgusted by the irresponsible and talkative Honda, serious class representative Mami has been avoiding him. However, even when Mami begins avoiding him even more after a certain incident at the convenience store, Honda is undeterred. Annoyed by Honda's overly familiar behavior, Mami complains about him to her new friend Miharu, who suggests they discuss the issue with Honda's friend Mishima.

Miharu is scheduled to take time off school and transfer to another hospital for surgery. She feels both anxious about the upcoming procedure and sad to be moving away from her friends. Seeing Miharu in her emotional state, Mishima resolves to participate in his first meet as a regular on the swim team, but the event falls on the same day as Miharu's transfer. As Mishima heads to the meet, he leaves a certain object with Honda.

Mishima has been concerned since Miharu went to the hospital and visits her every day. Honda and Mami are naturally worried about Miharu as well, but they're also concerned about Mishima. One day, Miharu's mother explains to Mishima the events surrounding that day from his childhood. What is the truth behind the memory Mishima has treasured since he was a boy?

Mishima has been unable to focus during swim practice since the new semester started. Though his relationship with Miharu has returned to normal, he still feels as though something is lacking. Meanwhile, Miharu begins missing school for some reason. Mishima is worried but unable to get in touch with her...

New students at Aokisora High School Mishima Haruki and Honda Towa are best friends. Honda oftens stays over at Mishima's house after coming over to hang out. At a convenience store near their high school, Mishima runs into his classmate Mashiki Miharu, a girl he's recognized since he was little. Though they've never spoken much before, when Miharu accidentally knocks over a bunch of products, Mishima helps her put them back without a word. Meanwhile, Honda is being avoided by Mihashi Mami, the other class representative...

As part of a special test, the school has brought the students to an uninhabited tropical island where they must now live for a week. Their performance on the test can have an enormous impact on the point standings of the four classes.

It's summer vacation! The first-years get to board a luxury cruise ship, where they're allowed to sample the highest class facilities available.

Even during summer vacation, lone wolf Horikita would rather remain locked in her room studying than interacting with others. One day, Ayanokoji invites her to visit the pool with some of the others.

Sakura's testimony has bought Class D time, but Horikita and Ayanokoji still need to find a way to tilt things in their favor. Meanwhile, Sakura senses the presence of a strange man nearby.

With the hearing for the assault approaching, Ayanokoji and Kushida attempt to secure the cooperation of Sakura Airi, possibly the only person who can testify that Sudo was acting in self defense.

Sudo has been accused of fighting with a student from Class C, and depending on an upcoming ruling, Class D might have its few remaining points stripped away.

Thanks to a lot of hard work and scheming, Class D managed to get surprisingly high scores on their midterm exam. But when a student fails a single test, Ayanokoji makes one final play to save his classmate from expulsion.

With their first midterm exam approaching, Class D needs to find a way to improve their class average, or face another month with no points to spend. Even Horikita decides to take part, forming a study group to help the class underachievers. But can the stanoffish Horikita really inspire her classmates to succeed?

Ibuki has stolen the key card, and Horikita's condition has deteriorated. Over Horikita's objections, Ayanokoji forces her to drop out.

With the panty thief incident already eroding Class D's trust, Horikita finds her leader key card stolen. While they try to figure out who did it, the base camp is thrown into chaos with a new incident of arson.

Class D has achieved a degree of unity in facing the special test, so Ayanokoji and Horikita head out to see how the other classes are getting along. Class B is working together to make a comfortable life for themselves, while Class A remains secretive.