Butei (Armed Detective) is a national qualification established by Intergovernmental Armed Detective Alliance (IADA) to combat the worsening global crime rate. They are allowed to bear arms, use supernatural abilities, and have the authority to arrest people if they have a Butei License. A Butei License may be obtained by attending a Butei education institution or starting a militant organization like the GIII League or Tohyama Warrior Office.

Other than the detective sector, even lawyers and prosecutors are obligated to obtain the arms qualification labeling them Armed Lawyer (武装弁護士 Busou Bengoushi?) and Armed Prosecuter (武装検事 Busou Kenji?)


Main article: Butei Law

Much like police officers, Butei'a are not above the law. They must follow a strict charter and operational procedures established by the IADA, which has variation depending on each country. Also, each Butei must have a Butei license to carry arms and make arrests legally. 

Butei Ranks

Main article: Butei Ranks

To measure a Butei's skill, they are all broken down by Ranks E to S. Typically their ranks are first acquired from studying in a Butei academy, but can improve or erode based on tests taken throughout the year or transferring between departments. On special circumstance the government may recommend the top Butei's be awarded a R rank, a rank beyond S rank.

Butei High School Curriculum

Main article: Butei High School Curriculum

The Butei educational facilities are similar to universities by having basic academic classes along with specialized classes according to each department including the opportunities to take jobs for credit. Also, it allows for non-high school student to intern.


According to Kinji, the existence of Butei can trace its roots to Sherlock Holmes himself. While he personally did not oversee the creation of the Butei nor train any students, his efforts laid the foundation for generations of Butei to come. Despite Holmes hailing from England, it would seem that the overarching headquarters of the Butei is centered in Rome.

Butei School Locations

  • Tokyo Butei High School (Academy Island)
  • Rome Butei High School
  • London Butei High School
  • Hong Kong Butei High School
  • Nagoya Butei Girl's Academy (Japan)
  • New York Butei High School
  • Manchester Butei High School
  • Warsaw Butei High School
  • Washington D.C Butei High School
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