Eri Kisaki, legally separated from Kogoro Mouri for ten years yet retaining his surname, is Ran Mouri's mother. She maintains lingering romantic feelings for Kogoro and frequently tests his regard for her. Their separation followed an incident where Kogoro shot her leg to save her from a serial killer—an act she respected as necessary—but she left after he criticized her inedible cooking during a gratitude dinner. Professionally, she uses her maiden name Kisaki, though legal documents like hospital records confirm her as Mouri. During high school, Eri and Yukiko Kudo tied in a "Miss Teitan High School" pageant due to Kogoro's delayed vote; his misunderstanding of "Miss" as "mistake," intending to vote for Eri, later angered her. Despite their rivalry, Eri and Yukiko remained close friends, facilitating playdates between their children, Ran and Shinichi Kudo. Shinichi recalls Eri frequently scolding him for mischief. A highly accomplished defense attorney known as the "Queen of the Courtroom" (a title playing on her maiden name "Kisaki," meaning "queen," and referencing author Ellery Queen), Eri possesses exceptional intellect. She achieved a perfect score on the Tokyo College entrance exam and received a Harvard recommendation at age 16. Her sharp deductive abilities often assist investigations, solving cases independently or alongside Conan Edogawa. She typically accepts clients with criminal backgrounds only upon detecting mitigating circumstances or case relevance. Physically, Eri is tall, slender, and strikingly attractive, often receiving but rejecting advances due to her enduring affection for Kogoro. She wears long brown hair in a bun, dons business suits, and uses glasses. She deeply cherishes her Russian Blue cat, Goro, named after Kogoro for their behavioral similarities. Her personality blends professionalism with personal warmth. She demonstrates care through actions like supporting Kogoro and Ran during Ran's amnesia. She offers Ran relationship advice, jokingly cautioning against detectives. Skilled in judo—taught by Kogoro—she employs ippon seoi-nage (one-arm shoulder throw) against assailants. Conversely, she is notoriously poor at cooking, a canonical trait confirmed by series creator Gosho Aoyama. In "Detective Conan Episode One: The Great Detective Turned Small," Eri appears as core cast, her interactions reflecting her established dynamic with Kogoro and Ran without unique plot developments.