Anna Akechi. 16 years old. Mikuru's partner with a bright and cheerful personality. She hates losing at anything and lives for one-on-one showdowns. She loves sweets and often hangs out with Jet-senpai and Mikuru. Her catchphrase is "Gold-star solution!"

Mikuru Kobayashi. 17 years old. A big sister figure to everyone and Anna's partner. Usually quiet, but has absolute confidence in her deductive reasoning. She actually loves cute things. She admires Sherlock Holmes, but can be a bit airheaded at times, which is when Anna steps in to help.

Ruruka Moria. 16 years old. A mysterious and somehow charming detective. She originally quit being a master detective to help Claire recover her memories, but after succeeding, she decided to join the Cure-at Detective Agency. She actually loves ice cream more than anything, which occasionally gives her an upset stomach.

Claire Hoba. 18 years old. Formerly part of the "Strongest Master Detective" duo with Ruruka. She had lost her memories, but with the help of Ruruka, Anna, and the others, she regained them and decided to join the Cure-at Detective Agency. She likes eclairs and her hobby is baking bread.

Jet-senpai. 12 years old. A genius inventor at a young age; he makes almost all the detective gadgets himself. However, there's always a flaw somewhere... He was an orphan taken in and raised by Mikuru, so they are basically family (?). Even though he's younger, he gets happy when called "Senpai," so you have no choice but to call him that.