TV-Series
Description
Hiro Kurusu is a supporting character in the koto music club at Tokise High School. She has wavy, medium-length light-brown hair swept to the right side and brown eyes. She wears two earrings on her right ear and enjoys having her nails done, though she trims them to play the koto. Her typical school uniform consists of a white blouse with a red and orange striped bow tie, a checkered brown skirt, blue socks, and brown shoes, often paired with a beige vest. She generally does not wear the school jacket except for performances. Her height is 161 centimeters, her birthday is October 19, and her blood type is A.

Hiro first appears as a second-year student who joins the koto club after being moved by their morning assembly performance. However, her initial motivation for joining is not genuine friendship or a love for music. Her past holds the key to her behavior: during junior high school, a new female student spread rumors that destroyed Hiro's friendships and caused her to lose her boyfriend. Witnessing how quickly those close to her turned against her based on a stranger's words, Hiro came to believe that human relationships are superficial and easily breakable. As a result, she developed a habit of infiltrating friend groups and using lies to break them apart, finding a cynical satisfaction in proving that trust and friendship mean nothing.

Upon joining the koto club, Hiro attempts to employ the same tactics. She tries to drive a wedge between members by spreading false claims about Satowa Hozuki, suggesting that Hozuki looks down on the other members and only joined the club because she had nowhere else to practice after being disowned by her prestigious family. However, the club's response defies her expectations. Instead of turning against Hozuki, the members thank her for being honest and reaffirm their trust in her. Club president Takezo Kurata, rather than getting angry, calmly tells Hiro that she must have a lot of free time to go to such lengths, a remark that finally pierces through her defenses and causes her to run away in tears.

This moment marks the beginning of Hiro's transformation. Kurata later approaches her again, not to scold her, but to offer to listen to her reasons if she is willing to share them. Satowa Hozuki also reaches out, telling Hiro that she sees similarities between them, as Hozuki also initially joined the club seeking something she had envied in their performance. With this support, Hiro finds the courage to return to the clubroom, apologize, and become a true member of the group. After her heel-face turn, she commits herself fully to the club and reverts to what seems to have been her natural personality before her past betrayal: a genuinely kind and honest girl.

In her role within the story, Hiro becomes the vice-president of the koto club. She brings prior knowledge of the instrument, having learned about it from her grandmother. She often practices the same parts as fellow member Kota Mizuhara and helps him learn rhythms and improve his playing. She shows deep care for her clubmates, crying when she fears she may have been responsible for Kota running away during a training camp or worrying that she caused an injury to Chika Kudo's hand.

Her most significant relationship develops with Takezo Kurata, the club president. What begins with her antagonistic actions toward him gradually deepens into mutual affection. She visits his home to encourage him not to carry the burden of leading the club alone, telling him he does not have to handle every problem by himself. Their chemistry becomes noticeable to others, and her family's inn serves as the location for the club's summer training camp. During a shopping trip, when they encounter people from her painful past who attempt to slander her, Kurata defends her without hesitation, telling them he is a better judge of character than they are and pulling her away by the hand. These moments leave Hiro visibly flustered as she struggles to understand her own growing feelings.

Hiro's development is one of learning to trust again. The unwavering bonds she witnesses within the koto club gradually tear down the defensive layers she had built around herself. She moves from being a cynical outsider who sought to destroy relationships to a dedicated and caring member who supports her friends and finds a sense of belonging for the first time since her painful experiences in middle school. Her notable abilities include her skill on the koto, developed through dedication to club practice, and her role as a reliable vice-president who helps lead the group alongside Kurata.