Midterm exams are finally over, leaving some students overjoyed and others depressed, and now it's time to decide who will participate in which events at the school's upcoming athletic festival. Riri is selected as the anchor for the swimming event, but Erika nominates Komichi for the same position, so the two girls compete to determine who will be the anchor. Riri is a member of the swimming club, and once made it to nationals in elementary school, and Komichi feels no desire to compete against her as rivals. Then Riri proposes that if she wins, she and Komichi should swap uniforms...

Komichi was chosen to lead a group in buying supplies for the athletic festival. On the weekend, she joins Erika, Touko, and Tomono to shop at a large mall. As a local who's been to this mall many times, Komichi is excited to act as their guide, but Touko, who's into fashion and accessorizing, knows more than she does about the shops. They visit a bookstore, where Erika picks up a book happens to be written by an author Tomono likes. In fact, Tomono had just finished reading it on the way to the mall. So she offers to lend it to Erika, but then she realizes the bookmark she had left in it is gone...