Uruka Takemoto has been a friend of Nariyuki's since middle school and is a swimming prodigy who should have a brilliant future ahead of her, but her academic grades are so bad that she's in danger of losing the college scholarship she's counting on. The academy's headmaster orders Nariyuki to tutor her, too. Uruka hates studying but suddenly becomes eager when she hears that Nariyuki is going to be her tutor. Actually, she's been in love with Nariyuki since middle school which is when he started helping her. Aware of her fellow mentees, Fumino and Rizu, Uruka secretly gets fired up.

The results of Nariyuki’s tutoring are about to be put to the test with the midterm exams. If the girls don’t raise their grades, they’ll get a new tutor. The three of them want to keep Nariyuki, though, so they become even more resolved to study hard for the exams.

Fumino is determined to go on a diet after a sudden weight gain. Rizu's self-proclaimed rival, Sawako Sekijo, has the wrong idea that the reason Rizu has set her sights on humanities is because she's in love with Nariyuki, and she tries to test Rizu's "love."

Ichinose Academy’s famous three-day, two-night study training camp has begun. Nariyuki and the students study hard at the boarding house in the mountains, but Rizu can’t stop thinking about her tutor.

Nariyuki is summoned by Mafuyu Kirisu, the girls’ former tutor, who interrogates him about the camp incidents. A worried Fumino, waiting outside the student guidance counselor's door, hears snatches of the conversation, including the expression "illicit sexual conduct."

While Nariyuki and Fumino are talking to each other behind the school, she loses her balance and falls into Nariyuki’s arms. Rizu apparently sees the "hugging" part and looks furious.

After Nariyuki wins a smartphone in a lottery, he can't wait to use it for apps like the dictionary, schedule managing, and the like. He also learns that studying in the bathtub is effective and quickly puts the method into practice.

When Nariyuki is walking by Mafuyu's apartment one day, she invites him in because she apparently had seen a cockroach. He goes inside and finds the place just as messy as it was during his last visit.

As a reward for being a tutor, Nariyuki gets to take a short summer course at an entrance exam prep school. He's eager to take the course in order to improve his results, but he meets Asumi Kominami, an academy alumni who is still studying to get into a university.

Downtown at night, Ms. Kirisu finds Nariyuki as he's about to enter a suspicious café and calls him to a halt. It's the maid café where Ms. Kirisu's former student, Asumi, works part-time.

Nariyuki consults Fumino about how his relationship with Uruka has become awkward, but he claims he's asking "for a friend." Right after that, Uruka comes to Fumino to discuss the same issue.

When Nariyuki goes to a festival, he runs into Uruka and strolls with her past the food stalls, helps Rizu deliver food, and takes an injured Mafuyu to Asumi's father's first-aid tent. In other words, as ever, he's a busy do-gooder.