During her student days, Himari married her husband who was also on the swim team. After three years of marriage, due to her husband's injury and their wedding, she had distanced herself from swimming. However, seeing a junior from the same school achieve good results stirred feelings of nostalgia, leading her to visit a swim class. On the observation day, she reunited with a classmate, Yamaguchi, who had become a coach. Himari, who was struggling with her relationship with her husband, began attending the swim class after being touched by Yamaguchi's thoughtfulness. Himari gradually became drawn to Yamaguchi's kindness and strength, crossing the line of friendship...
