Reika Ryuzaki, known universally by her nickname Madame Butterfly, is a senior student and the star player of the Nishi High School tennis team. Her nickname, Ochoufujin, was earned because of her exceptional grace and elegance on the court, which makes her stand out as the team’s most accomplished and admired athlete. It is her poise and skill during a match that first captivates the protagonist, Hiromi Oka, and inspires Hiromi to take up tennis in earnest. As the top player, Madame Butterfly is the benchmark against which all other team members measure themselves, and she carries herself with a quiet confidence that reflects her status.

Motivationally, Madame Butterfly is driven by a desire to maintain her position as the team’s ace and to uphold the high standards of her own play. Her pride in her abilities is evident, and she takes her role as a senior role model seriously, though she can be cold or distant toward those she deems unworthy of her attention. Her relationship with Hiromi evolves from that of an unattainable idol to a direct rival once Hiromi begins receiving special training from the new coach, Jin Munakata. This shift creates tension between the two, as Madame Butterfly is initially dismissive of Hiromi’s potential and threatened by her rapid improvement. Later, she becomes a formidable opponent in key matches, pushing Hiromi to grow stronger.

She also interacts with other strong players, such as Ranko Midorikawa, who once pushes her to the brink of defeat, showing that even the elegant ace is not invincible. Her relationships with her teammates are marked by a mixture of deference and fear, as her skill sets her apart. In terms of development, Madame Butterfly undergoes a subtle arc: she begins as an untouchable star, but through her encounters with Hiromi and other challengers, she is forced to confront her own limits and the possibility of being surpassed. This pressures her to refine her game and reaffirm her dedication to tennis.

Notable abilities include a powerful serve, which she uses to dominate rallies, and an overall playing style that merges technical precision with fluid, almost dance-like movement. Her grace is not merely aesthetic; it reflects her complete control over the court. While she may initially appear aloof, her actions consistently demonstrate that she is a serious competitor who respects strength in others once it is proven.