Kimihiko Kimizuka

Kimihiko Kimizuka is an ordinary-looking teenage boy. He does not have standout features, and his style is simple, reflecting his desire for a normal life. No detailed information about his physical appearance was given.

Kimihiko often says, "This is unreasonable," showing his frustration with sudden trouble. He is calm in tense situations because he is used to getting involved in chaos. While he keeps a cool head, he is passionate when his friends are in danger. He dislikes self-sacrifice and wants to save people close to him. Kimihiko is quick-thinking, clever, and has learned to handle himself in a fight, even if he is not as strong as some of his partners.

Kimihiko was born in Japan on May 5, and his parents disappeared soon after his birth. Because of his problematic "trouble magnet" nature, he moved between many institutions as a child. He became Siesta’s assistant after being swept into an airplane hijacking. For three years, he traveled with Siesta, fighting the "Enemies of the World." After Siesta’s death, he tried to blend into normal high school life but was soon pulled back into adventure when Nagisa Natsunagi asked for his help.

Kimihiko is called a "Singularity," a special existence who can change the world’s destiny. He is skilled in opening locks and using handguns, and can defend himself in combat. For a time, he gained an invisibility ability by swallowing Chameleon's "seed," though he later lost this power. His main strength is his knack for getting caught in events that change the world, even when he tries to avoid them.

• Siesta: Kimihiko’s partner and the original "legendary detective." Their bond is deep, based on trust and promise. Even after her death, he wants to bring her back to life.
• Nagisa Natsunagi: A classmate who asked Kimihiko for help, pulling him out of his slump. She becomes an important partner.
• Charlotte Arisaka Anderson: At first, they argue a lot, but eventually become close friends.
• Yui Saikawa: Another close ally.
• Hel, Fūbi Kase, others: Kimihiko meets and befriends many through his adventures, often owing to his trouble-magnet nature.

• Kimihiko loves detectives and idols but dislikes agents, green peas, getting up in winter, powdered medicine, pigeons, and crows.
• His career is "assistant," usually helping detectives.
• He is known as a favorite character of the author.
• He ranked well in the "Kono Light Novel ga Sugoi!" awards for male characters for several years.

“This is unreasonable.”

“Listen up! I won’t give up on you! Even if you’re happy with this ending, I’ll never accept it! Maybe no one will understand me! Not even Nagisa! Not even Yui! Not even Charlotte! Maybe what I’m doing goes against the world itself! But I’ll definitely bring you back to life someday! I promise!”

Meeting Siesta

Four years before the story, Kimihiko is pushed onto a plane by men in black. An announcement asks for a detective onboard. Siesta, his seat neighbor, says she is a detective and asks Kimihiko to help her as her assistant. They solve a hijacking together and later go on a “date” at his school’s festival, which turns into another messy event. Siesta promises to protect him, and he becomes her assistant, unsure why he agreed.

Three Years of Adventure

For three years, Kimihiko travels the world with Siesta. They visit places like America and Singapore and handle requests from important people, all while fighting bio-humans. Most of these journeys’ details are unclear, except for a few festivals and battles.

After Siesta’s Death

Following Siesta’s death, Kimihiko tries to live quietly. Nagisa Natsunagi approaches him for help, and he meets new friends and foes. Aboard a cruise ship, Nagisa shows traits of Siesta’s personality. Together, the group faces new challenges, solves mysteries, and deals with guilt and responsibility.

The Forbidden Wish

During a crisis, Kimihiko accepts part of Nagisa’s guilt and fights to help her. He briefly gains invisibility by using Chameleon’s seed, though it is risky. Despite concerns, he makes a bold promise: he will bring Siesta back to life no matter what, even if it defies the world.

Journey to London

To fulfill his promise, Kimihiko travels to London with Nagisa, chasing clues and encountering more adventures, including another confrontation with a major enemy called Seed. They receive help from the psychic Mia Whitlock and uncover secrets left by Siesta.

Siesta’s Return and Farewell

Thanks to sacrifices from Nagisa, Siesta comes back to life, but Nagisa dies. Kimihiko mourns, but Siesta helps him move forward. Together, they fight Seed and win, reviving Nagisa. After this, Kimihiko learns more about being a Singularity and attends a secret government meeting. There, he learns that some want to eliminate him to avoid world chaos.

Meeting the Mentor

As a child, Kimihiko lived in different places and was cared for by a mysterious man named Danny Bryant, who became his guardian for a while. Kimihiko also meets Tsukika Shirogane, who searches for the missing Danny.

Happy Days

Years later, Kimihiko, Siesta, and Nagisa open the Shirogane Detective Agency and live peacefully, rarely getting requests. He wishes for peaceful days for his friends, though he gets drawn into more dangerous events like the Holy Return Ritual in France, where secrets and new cases appear.

Searching the Past

With Siesta and Nagisa, Kimihiko investigates their own pasts. By touching special artifacts called "Holy Relics," he gets visions that help them uncover mysteries about Singularity, Detective, and Phantom Thief Abel—an enemy who can rewrite reality. Kimihiko learns about his power to change fate and the dangers it brings.

Ongoing Mysteries

Kimihiko continues searching for missing friends like Charlotte and faces secret organizations and hidden truths. As of the tenth novel, some mysteries remain unsolved.

• Kimihiko is called a “Singularity,” someone who can change history during critical times.
• Some leaders think it might be better to get rid of him before he causes more world-altering events.
• His life is a constant mix of ordinary dreams and extraordinary adventures, always pulled by his mysterious fate.