Itsuki Hashima is a light novelist obsessed with little sisters, strictly focusing on them when he writes his stories. Despite his personality, he's surrounded by a tight circle of friends, including a beautiful genius writer who loves him, a big-sisterly college classmate, a fellow male writer, a sadistic tax accountant, his editor, and Chihiro, his perfect younger step-brother who takes care of the housework and cooking. As the story progresses, the underlying conflicts of dreams and goals ...