Konna Shousetsu, Kakanakereba Yokatta.

A childhood promise binds two people to be together always. Tsumugi and the narrator have remained inseparable since that time, expecting their bond to remain unshaken. However, Tsumugi, while hospitalized, asks the narrator to write a novel about a romance between her and a boy he once knew. This request marks the beginning of a shift in their relationship. Tsumugi's interest in love and fiction prompts questions about what she truly seeks. The story explores the evolving dynamics among the narrator, Tsumugi, and the boy from the past.