Yajiru-senpai is a cheerful and kind-hearted high school senior in Gunma Prefecture, renowned as a prominent member of her school's soba club. She burns with a passion for soba noodles, constantly experimenting with new recipes and eagerly sharing her creations with classmates. Her dedication drives her to actively recruit new members for the club, where she teaches traditional soba-making techniques and passionately highlights the dish's deep cultural roots in Gunma.

Her consistently uplifting and approachable nature earns her the admiration of peers and makes her exceptionally effective at promoting Gunma's local culture through these culinary traditions. This regional pride manifests clearly in her personal catchphrase: "I only eat food made in Gunma."

Her established role centers on embodying this local pride, functioning as a vehicle to showcase Gunma's distinct identity. Through her everyday interactions and dedicated club activities, she actively challenges negative stereotypes about the prefecture.