Kisaki Eri is the mother of Mouri Ran and the legally separated wife of Mouri Kogorou. She is a lawyer who frequently gets entangled in Mouris cases, often serving as an extra pair of eyes when it comes time to investigate a crime. Although she does not appreciate Mouris attitude and personality (especially his drinking and nanpa habits), she still deeply loves and cares for him, testing him to see if he still cares about her as well. Eri and Mouri have been best friends since childhood and fell in love in their teens. Ten years before the Detective Conan storyline began, they separated and took different paths in life. After separating, Eri focused on her legal career and has become a highly respected (and feared) member of her profession. She is considered incredibly attractive, with various men of all ages pining for her, but she always turns them down due to her feelings for Mouri. Along with Yukiko, Eri was one of the two most beautiful girls at Teitan High School when they were students. Despite their rivalry ending in a tie, the two remained close friends and often let little Shinichi and Ran play together and have playdates. Shinichi remembers how Eri would scold him for starting trouble.
Eris personality is suited to her career as a lawyer. She is very questioning and gets involved in the investigation of cases alongside Mouri, much to his dismay. She has a cat named Goro, which she cares for deeply, and is also very close friends with her secretary, Kuriyama Midori. Eri is highly intelligent and has a keen eye for detail, as well as being a skilled judoka, taught by Mouri himself. Her deductions are almost always accurate, and she often provides valuable advice to Ran on her relationship with Shinichi.