Kazuha Tooyama

Kazuha is energetic, caring, outspoken, superstitious, and fiercely loyal. She speaks in a strong Kansai dialect and rarely hesitates to argue with Heiji, especially when his detective work causes him to ignore danger or basic courtesy.

She is more emotionally transparent than Heiji but still struggles to state her romantic feelings directly. Jealousy frequently appears when another girl seems interested in him, while Heiji behaves similarly when another boy approaches Kazuha.

Kazuha also believes strongly in charms, omens, and supernatural possibilities. This contrasts with the more skeptical detectives around her and occasionally leaves her frightened during cases involving supposedly paranormal phenomena.

Kazuha holds a second-dan rank in aikido. She can execute throws, locks, and takedowns against larger opponents and is capable of defending herself against dangerous criminals.

Her martial arts emphasize control and redirection rather than Ran's karate-style striking. Heiji is well aware of her strength and takes her ability seriously.

Kazuha is also perceptive and quick-minded. Although not a detective, she can understand coded clues, remember important details, and contribute observations that assist an investigation.

Kazuha is introduced when Heiji's Osaka life begins overlapping more frequently with Conan's investigations. Her initial misunderstanding of Ran's relationship with Heiji quickly gives way to friendship once she realizes Ran is interested in Shinichi.

She subsequently becomes a regular member of the Osaka-centered cast and frequently accompanies Heiji to cases involving Conan and the Mouri family.

Her long-running romantic relationship with Heiji parallels the relationship between Ran and Shinichi, although Heiji's repeated failed attempts to create an ideal confession become a recurring source of comedy and frustration.

Heiji Hattori is Kazuha's childhood friend, best friend, and mutual romantic interest. Their relationship combines constant bickering with deep trust and protectiveness.

Ran Mouri becomes one of Kazuha's closest friends. Kazuha Tooyama and Ran Mouri frequently discuss their respective feelings for Heiji and Shinichi.

Conan Edogawa is a regular companion during Kazuha's visits to Tokyo and the cases she shares with Heiji.

Ginshiro Toyama is Kazuha's father and a senior Osaka police officer.

Momiji Ooka considers herself Kazuha's romantic rival for Heiji's affection, creating considerable tension between the two girls.