W Wish

Junna and Senna are twin siblings that live alone. Shortly after the exams, there will be a Cherry Blossom Summer Festival at school, and Senna is excited to create memories with a relunctant Junna. Junna's homeroom teacher calls the twins over to the office to propose that they could live at the school because she is concerned about their situation. Junna doesn't recall the memories of the accident in which his parents died, but he refuses saying that he is encouraged to work hard to support his living because of Senna's existence.

Akino, the class representative of Junna's class, has decided that the theme of their activity for the Cherry Blossom Summer Festival is a haunted house. While the class groans, a student named Sana appears at Junna's class and asks him to come with her to the Helpers Club (formerly the Literature Club). It turns out that the president of the club is the most popular girl at the school, Tsubasa. Tsubasa explains the purpose of the club was to help others, and with the preparations for the Cherry Blossom Summer Festival, she believes that this is a good opportunity to get more members. She requests for Junna's help, knowing him to be very hard-working to support himself and his sister. Flattered, Junna accepts, and is given the job to collect news on the all activities in the festival. Meanwhile, Senna, who had spotted Sana dragging Junna, had eavesdropped on the conversation and is slightly bothered by it.

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.

Senna is disquieted at how much time Junna and Haruhi are spending together. Akino asks Senna for assistance because she cannot locate Junna to ask for his. She explains that the haunted house is short on decorations, and since Junna and Senna's parents are archaeologists, they might have materials that they could use. Senna leads Akino and Tomokazu to the mansion-like home she and Junna live in, and reluctantly gives Akino permission to borrow artifacts. When Tomokazu brings up the topic of club members staying at school overnight to finish constructing their club activities, Senna decides to go, despite the Cooking Club being ready. Meanwhile, Haruhi asks Junna to be her date for the Cherry Blossom Summer Festival, but Junna declines because he doesn't remember too much about her.

While making the last touches to the haunted house at night, Akino suddenly injures her leg and Junna carries her away. Haruhi becomes jealous and tries to hurt herself so Junna will carry her as well. Senna is angry that Haruhi is causing so much trouble and confronts her, and before their argument escalates, Yuuko arrives and orders Haruhi to go home. Relieved, Junna takes a break at the school roof from his work, where he sees Tomo. As the two stargaze, Tomo sagely tells Junna not to be afraid because she will always watch over him. Senna comes to the school roof, causing Junna to end his break, and she asks him if they'll be together as siblings. Junna agrees, and the two help finish the haunted house.

Senna wakes Junna up for the Cherry Blossom Summer Festival. Just as Junna promised, the two spend the entire festival together. When Haruhi shows up, she cannot locate Junna, and Junna does not hear her calling for him. When night falls, Senna tells Junna that she's happy he kept their promise, but an image of Haruhi flashes through his mind. Junna is suddenly concerned about Haruhi and his past, but Senna tries to reassure him that he doesn't need to remember everything. Just as the fireworks begin, Junna's memory suddenly flashes before his eyes, causing him to pass out.