Following his father's remarriage, Yuuta Asamura gains a stepsister named Saki Ayase, who is recognized as the most beautiful girl in their grade. They agree to maintain a relationship at arm's length—neither too close nor too distant—based on the lessons learned from their parents' past relationships. Saki has long been independent, managing her family's needs without relying on others, while Yuuta struggles to connect with her sincerely. Nevertheless, they establish a peaceful coexistence, gradually finding comfort in each other's presence. Their bond slowly shifts from that of strangers to friendship, hinting at a potential romantic future ahead.
