While Rei is reeling over Yoshino's shocking announcement, the bulk of the school copies them by breaking their soeur relationships too. Tori Eriko, Rei's soeur, isn't even aware of the problem due to her odd behavior and suspiscious absence from school. Yumi goes to the hospital to talk with Yoshino, and learns the true nature of the Yellow Rose soeurs. Yoshino tells her all about her plan to make Rei a stronger person.

Uzawa Mifuyu narrates her past as Sachiko's desperate admirer and her reasoning behind her decision to not claim the treasure hunt's prize. She finally acknowledges that Yumi is a better match for Sachiko than her, and quietly slips out of their lives and the series.

Tsutako and Minako's papparazzi-like plans wear them out while Shimako comes to an understanding with both Sei and Rosa Canina. The dates ultimately strengthen Yumi and Yoshino's relationship with their soeurs and reaffirm the place they stand in their older sister's lives.

In the days before graduation, Rosa Chinesis and Rosa Foetida leave their parting words to their petite soeurs and grande-soeurs. Yumi begins to worry why Rosa Gigantea hasn't done the same. She swears to Sei she'd look after Shimako and promises to do anything as her final request, and Sei's answer leads to a surprisingly sweet moment and a revelation about her future.

Shimako and Noriko become even closer, but a shocking revelation about Shimako's true religion is announced in front of the entire school, testing their relationship. Meanwhile, the Yamayuri Council is concerned over the state of Shimako's well-being and decide to take matters into their own hands.

Yumi and Sachiko finally go on their date to the amusement park. However, Kashiwagi and Yuuki turn up, with Kashiwagi bearing a certain agenda in mind. Yumi learns a few things and Kashiwagi's intentions are made clear.