Shiratori’s debut was in the first movie, The Clockwork Skyscraper, acting as a member of Megure’s police force. At first, Shiratori only appeared in movie roles, playing key roles in the first three Detective Conan movies. At some point, Shiratori later became a full-fledged inspector.
As a child, Shiratori studied diligently to one day become a lawyer, and had even memorized some laws by heart. One day, he witnessed a young girl confronting two juveniles trying to steal mangas from a bookstore. To thank him for helping her out, the girl bought him a drink and made a sakura petal pattern from the straw wrapper, saying the sakura was the symbol of courage for the Japanese police (due to the distinct form of the Japanese police badge). It was because of this incident that Shiratori decided to become a cop rather than a lawyer.
Shiratori later joined the Tokyo Metropolian Police Department and worked alongside Inspector Megure, often acting as an extra officer or pair of eyes, though he later became an inspector of his own. When Satou Miwako joined the department, Shiratori believed that he had found his childhood love again, and as a result both he and his younger colleague Takagi considered each other rivals for Satou’s affections. Shiratori would often try to show off in front of Takagi by asking Satou on a date, but she always rejected him, much to his dismay. However, he has since come to date Kobayashi Sumiko, whom he finally discovered to be his true love.
As a cop, Shiratori is fairly average. He is calmer on the case than Takagi or Satou. Shiratori, like Satou and Takagi, believes that Conan has a lot of intelligence for a boy his age, but unlike Takagi and Satou, he usually tends to care not much for Conan’s opinion. He often feels that Conan gets in the way, though Conan always proves otherwise. However, unlike Kogorou, Shiratori will take notice and suspect something if Conan points something quite interesting. Shiratori’s attitude can appear cocky when battling for Satou’s affections, but otherwise he appears more modest, as in the first Detective Conan movies or when he is with is now girlfriend Kobayashi Sensei.