Kyōtarō Kakei is the main protagonist of A Good Librarian Like a Good Shepherd. He is a diligent and reserved second-year high school student at Shiomi Academy, a prestigious institution renowned for its vast library. Kakei’s greatest passion is reading, and he spends almost all his free time with books, even filling his dormitory room entirely with them. He is the sole member of the school’s Library Club, a position he values because it allows him to read in peace without interacting with others more than necessary.

Kakei comes across as a quiet, observant young man who prefers solitude and avoids unnecessary social involvement. He is academically excellent and has been an honor student since his early school years, though he finds this status ordinary and unexciting. His decision to enroll at Shiomi Academy was driven by his desire to access its large library and the rumored hidden magical shelves within. Despite his introverted nature, he is fundamentally kind-hearted and possesses a strong sense of responsibility. He tends to be pragmatic and sometimes acts as a fun-killer when the club suggests leisure activities, but he gradually becomes more open to the enjoyment of shared experiences.

His motivations are rooted in a childhood aspiration: he wished to read all the magic books in the world, which were kept in a magical library. To enter that library, he was given a bookmark by a figure known as the Shepherd, which served as his entry ticket. The condition for using the bookmark is that he must show kindness and bring happiness to the people he encounters. This promise drives him to help others, even when he initially resists involvement.

The story begins when Kakei receives a mysterious text message from the Shepherd, predicting that his fate will change that day. Shortly after, he uses his acute sixth sense to save a classmate, Tsugumi Shirasaki, from a tram derailment. Tsugumi later joins the Library Club and proposes the Shiomi Happy Project, an initiative to make the academy a more enjoyable place. Kakei reluctantly agrees to help, and under the Shepherd’s guidance, more female students join the club: the wealthy and talented Tamamo Sakuraba, the famous singer Senri Misono, the energetic athlete Kana Suzuki, and the quiet but observant Nagi Kodachi. Although Kakei is not officially the club president, the other members consistently rely on him for advice and leadership.

Kakei’s relationships with these girls form the emotional core of the narrative. His bond with Tsugumi is particularly close, as she is the one who draws him out of his shell and encourages him to engage with others. The diverse personalities of the club members challenge his solitary nature and gradually soften his demeanor. Over the course of the story, Kakei develops from a detached bookworm into a more sociable and empathetic individual who genuinely cares for his friends and takes responsibility for their well-being.

In terms of abilities, Kakei possesses a unique sixth sense that allows him to perceive impending events or sense danger, which he first demonstrates by predicting the tram accident. This intuition is linked to the Shepherd’s bookmark and the hidden magic library. He is also highly knowledgeable about a wide range of subjects due to his extensive reading, and he often uses this knowledge to help solve the club members’ problems. His calm and analytical nature makes him an effective mediator and problem-solver, though he remains humble and does not seek recognition.