After his father remarried, Yuuta Asamura found himself with a new stepsister, the stunningly beautiful Saki Ayase. In an ironic twist, Saki also happens to be the most sought-after girl at their school. However, due to their parents' past relationships, the pair decided to keep a safe distance from each other instead of getting too close or becoming rivals. Saki, who had always taken care of her family alone, struggled with relying on others, while Yuuta found it difficult to figure out the appropriate way to treat her. As they lived together, they gradually adapted to each other's presence and began to find comfort in each other's company as equals. Over time, they transformed from strangers to acquaintances, and who knows, maybe their relationship could even turn toward love someday.