After her parents’ separation, Shima Sumitomo stayed with her mother but felt uneasy around her stepfather and struggled to connect with peers at her high school. Seeking a fresh start, she relocates to Hokkaido to live with her father. At her new school, she encounters Gen Tatebayashi and Wao Sakurai, the most admired boys there. The school has a unique rule stating that “Gen and Wao belong to everyone,” and anyone who violates this rule faces social exclusion. Despite this, Shima finds herself growing closer to both Gen and Wao.