Titre original : Another Sister
Junna runs into Tomo, an anti-social classmate of his who refuses to participate in the class activity. In response to this, Junna encourages her to assist and manages to help land her in a suitable role for the haunted house. Junna goes to report the Cooking Club's activity, where Tomokazu, Tomo's identical twin brother, embraces him. When Junna pushes away Tomokazu, Tomokazu's apron is accidentally soaked with soy sauce. Both Tomokazu and Senna are disappointed by this because they have to make more aprons for the rest of the club members. At the sound of trouble, Sana quickly arrives to help, but she ends up causing a fire, resulting in the arrival of the police. The officer, Yuuko, scolds the group, but also tells Junna that she had brought along his childhood friend. Junna and Senna are led outside to meet this new girl, and in turn, she addresses Junna as her older brother and hugs him. Although Junna does not remember who she is, he remembers her name, and this worries Senna.