Yui Uehara

Yui is observant, courageous, compassionate, and generally more approachable than Kansuke. She handles suspects professionally while remaining capable of matching her colleagues' determination when an investigation becomes dangerous.

Her familiarity with Kansuke occasionally overrides police formality. She calls him "Kan-chan," a childhood nickname he repeatedly tells her not to use while they are working.

Yui can be impulsive when someone close to her is involved. Her willingness to place herself inside a dangerous household to investigate a colleague's death demonstrates both courage and a tendency to shoulder risks personally.

Yui is an experienced police detective with strong investigative instincts. She can analyze evidence, interrogate witnesses, follow coded clues, and contribute meaningfully even when working beside exceptional deductive talents such as Kansuke, Takaaki, and Conan.

She possesses practical knowledge of Nagano's geography, local history, and communities, making her particularly effective during cases tied to the region.

Yui is also physically courageous and does not hesitate to enter dangerous environments while investigating suspects.

Yui is introduced during the Furinkazan case as a member of the Torada household rather than an active police detective. Her connection to Kansuke quickly reveals that she previously served with the Nagano police.

After Kansuke was presumed dead, Yui left the police and married Yoshiro Torada partly to investigate the suspicious death of fellow officer Kuroto Kai from inside the Torada family. Yoshiro is subsequently killed during the Furinkazan murders.

Once the case is resolved, Yui returns to the Nagano Prefectural Police and resumes working under Kansuke. She thereafter becomes a recurring investigator alongside Kansuke and Takaaki.

Kansuke Yamato is Yui's childhood friend, superior officer, and implied romantic interest. Yui has cared for Kansuke Yamato since childhood and continues calling him "Kan-chan" despite his objections.

Takaaki Morofushi is Yui's colleague and another member of Nagano's central investigative trio.

Kuroto Kai was a police officer admired by Yui and Kansuke when they were young. His example helped inspire both to enter law enforcement.

Yoshiro Torada becomes Yui's husband during the period when she has left the police. Yui's marriage also allows her to investigate the circumstances surrounding Kuroto Kai's death from within the Torada household.

Conan Edogawa repeatedly assists Yui and the other Nagano officers during complicated cases, and she recognizes his remarkable observational ability.