Now that the school's marriage training course has started, Jiro and Watanabe, who don't get along, become a couple. They decide to get along to reach A rank and change their couples.
Jiro, who realized that what happened between Watanabe and Tenjin was just a misunderstanding, the relationship between these two people gets better again. Meanwhile, the exam season begins.
Since a summer job together, Akari's determination, Shiori's racing heart, and Jiro's lack of answers have intensified their feelings. Then Jiro and Shiori meet at a bookstore.