Kyousuke Natsume is the leader and original driving force behind the Little Busters, a group formed to bring joy and unity among its members. Known for his charisma, intelligence, and playful nature, Kyousuke often proposes outrageous activities but usually follows up with rational explanations that bring deeper meaning to his actions. Beneath his lighthearted behavior lies a sharp and compassionate mind. He cares deeply for his younger sister, Rin Natsume, and expresses a strong brotherly attachment, often wishing she would affectionately call him onii-chan, though Rin insists on using his name instead.

Riki Naoe, the protagonist, looks up to Kyousuke as a mentor and guide. Even during the events of Refrain, Riki’s journey toward emotional strength mirrors Kyousuke’s influence and leadership. Unbeknownst to most of the group, Kyousuke had orchestrated events so that Komari Kamikita, Haruka Saigusa, Kudryavka Noumi, Yuiko Kurugaya, and Mio Nishizono would eventually become part of the Little Busters. His ultimate goal was to build an artificial world created with the help of others to strengthen Riki and Rin, preparing them to face the harsh reality of a tragic accident.

However, his methods unintentionally push Rin beyond her emotional limits, leading to a mental breakdown during the time loop. Deeply regretful, Kyousuke feigns a depressive state to motivate Riki to grow stronger, mirroring how Riki once fell into despair after the loss of his parents. As Riki gradually regains his strength and begins to reunite the group including Masato Inohara and Kengo Miyazawa Kyousuke returns to support him behind the scenes, even attempting to delay the bus explosion in the real world.

Eventually, after Riki successfully reforms the Little Busters, he invites Kyousuke back into the group just as Kyousuke had once done for him. Following a baseball game where Masato disappears, Kyousuke reveals the truth about the artificial world to Riki and Rin, helping them awaken and accept reality. Additionally, it is strongly implied that Kyousuke is Shun Tokikaze, the leader of the darkness executives in Saya Tokido’s route.

Kyousuke is a tall and striking young man with medium-length auburn hair and vivid red eyes, often described as resembling burning embers reflecting the intensity and passion that define his personality. His expressive features and confident presence contribute to his charismatic appeal.

He typically wears the standard male uniform of his school, consisting of a black jacket with red trim, a gold-accented white-collared shirt, and a blue tie. This attire is consistent with most male students, with the exception of Kengo Miyazawa, who dresses differently. Kyousuke is rarely seen out of uniform, except during baseball practice sessions with the Little Busters, where he wears more casual, sports-appropriate clothing.

Kyousuke Natsume founded the Little Busters during his childhood, forming the group with his close friends Masato Inohara, Kengo Miyazawa, and his younger sister, Rin Natsume. As the oldest among them, he naturally assumed the role of leader, often guiding the group with enthusiasm and creativity. His influence inspired others especially Riki Naoe, who joined later to find purpose and strength within their circle.

Later in the story, Kyousuke secretly helps construct an artificial world alongside others who survived a tragic bus accident. His goal is to mentally and emotionally prepare Riki and Rin to face the painful truth of their reality. Although his methods are well-intentioned, they push Rin beyond her emotional capacity, resulting in a temporary breakdown.

In Refrain, Kyousuke steps back and feigns a depressive state to push Riki to grow stronger and take on a leadership role. Eventually, Riki successfully reunites the group, and Kyousuke reveals the truth behind the artificial world, allowing Riki and Rin to awaken and accept reality. His actions throughout the series demonstrate a complex mixture of foresight, sacrifice, and unwavering devotion to his friends.

• Rin Natsume: Rin is Kyousuke’s younger sister, and he is deeply protective of her. He often tries to act like a doting older brother, expressing a desire for Rin to call him onii-chan, though she typically addresses him by name. His concern for her well-being drives many of his decisions, including the creation of the artificial world meant to help her grow stronger and face reality.

• Riki Naoe: Riki looks up to Kyousuke as a role model and older brother figure. Kyousuke is instrumental in Riki’s emotional development, guiding him through the challenges of adolescence and encouraging him to become more independent. Their bond is central to the series, especially in Refrain, where Kyousuke steps aside so Riki can assume the role of a leader.

• Masato Inohara and Kengo Miyazawa: As original members of the Little Busters, Masato and Kengo share a deep bond with Kyousuke. The trio, along with Riki and Rin, form the core group of friends. Kyousuke values their friendship greatly and often leads their activities, especially their shared love for baseball. Despite their occasional disagreements, he relies on them in both the real and artificial worlds.

The given name Kyousuke (恭介) is composed of the kanji kyou (恭), meaning “respectful” or “polite,” and suke (介), which can mean “forerunner” or “herald.” This reflects Kyousuke’s role as the admired leader and guiding force within the Little Busters.

His surname, Natsume (棗), translates to “jujube,” referring to Ziziphus jujuba, a species of fruit-bearing plant in the buckthorn family. Commonly known as jujube, red date, or Chinese date, the plant is known for its resilience and sweet fruit attributes that can be symbolically linked to Kyousuke’s strength and inner warmth.