Nana was a college classmate who married Takashi and built a happy family life. Living in company housing was comfortable, and Ryuichi, her husband's best friend who lived next door, was a great support to her. One day, an invitation arrived from a college alumni reunion. Since Takashi could not attend due to work, Nana and Ryuichi decided to go together. However, during the reunion, Nana found herself recalling feelings for Ryuichi that she thought she had long buried. Emotions beyond mere friendship began to resurface, leaving her deeply conflicted and unable to hide her inner turmoil.