A second-year student calling herself Rosa Canina runs against the en boutons in the Yamayuri Council elections with murky intentions. Todo Shimako hesitates to run at all due to her first-year status and her reluctance over taking a leading council position until a talk with Rosa Canina forces her to make a decision. Yumi confronts Sato Sei, Shimako's soeur, over her refusal to encourage Shimako to run, and learns more about the relationships between older and younger soeurs and how to best support Sachiko.