In the translation of this series, name are given in Euro-American style, i.e,
The series revolves around Reiko Himekawa. At the age of 29, she has become at Lieutenant and Squad Leader in the Tokyo Metropolitan Police Department (TMPD), which is a rapid rise, especially since she is a woman with no special connections. Normally, people don't make sergeant, the next lower rank, until 30, and some people resent her. She likes the hierarchical and clearcut nature of the police organization.
The Japanese police ranks in ascending order are:
A local police commander was the equal of a division head at the National Police Agency, while the director at any major department at the Metropolitan Police outranked the chief of any of the smaller prefectural headquarters. [from The Silent Dead, p. 16]