Kodaka Hasegawa, a transfer student to St. Chronica's Academy, has found it difficult to make friends because of his mix of brown-blond hair (inherited from his deceased English mother) and fierce-looking eyes that make him look like a delinquent. One day, he accidentally comes across the equally solitary and very abrasive Yozora Mikazuki as she converses with "Tomo", her "air" (imaginary) friend. Realizing that they lack social lives and skills, they decide that the best way to improve their situation is to form the Neighbors Club, "an after-school club for people with no friends like themselves".