Name: Iroha Gender: Female Akira Mikado's younger sister. First person: I (polite/feminine) No. 2 of the Tsukuyomi Detective Agency. Solves cases with incredible deductive reasoning. Usually blunt and tsundere, but shows her sweet side occasionally. Always being dragged around by Kaguya. Partners: Kaguya and Yachiyo. Appearance: Short hair with fox ears.

Name: Kaguya Gender: Female First person: Kaguya (referring to self by name) No. 3 of the Tsukuyomi Detective Agency. Has a lively personality and is always dragging Iroha along. Partners: Iroha and Yachiyo. Appearance: Super long blonde hair, rabbit ears.

Name: Yachiyo Tsukimi Gender: Female First person: I (polite/feminine) No. 1 and leader of the Tsukuyomi Detective Agency. Issues orders when a case occurs and occasionally helps those who are stuck. Usually calm, but terrifying when angered. Partners: Iroha and Kaguya. Appearance: White hair in twin tails.

Name: Akira Mikado Gender: Male First person: I (casual/masculine) Iroha's older brother, slightly overprotective of his sister. No. 4 of the Tsukuyomi Detective Agency. Forms the team "Black Onyx" with Rai and Noi to solve cases. Loves flashiness, so he corners criminals in a flamboyant style. Appearance: Red hair.

Name: Rai Gender: Male First person: I (casual/masculine) Noi's older brother. No. 5 of the Tsukuyomi Detective Agency. Forms the team "Black Onyx" with Akira and Noi to solve cases. Usually quiet, but goes along with the mood well. Appearance: Silver hair, wearing a robe.

Name: Noi Gender: Male First person: I (casual/masculine) Rai's younger brother. No. 6 of the Tsukuyomi Detective Agency. Forms the team "Black Onyx" with Akira and Rai to solve cases. Since he's lazy, he always drags the rookie Guest into cases when they arise. Appearance: Black hair with pink mesh in twin tails, white tiger ears.

Name: ROKA Gender: Female First person: I (polite/feminine) Receptionist for cases at the Tsukuyomi Detective Agency. Informs everyone of cases that come to the agency alongside Mamimami. Kind, but like Yachiyo, she is scary when angry. Appearance: Coral pink hair, deer antlers.

Name: Mamimami Gender: Female First person: I (polite/feminine) Receptionist for cases at the Tsukuyomi Detective Agency. Informs everyone of cases that come to the agency alongside ROKA. Usually easygoing, but becomes a different person when it comes to food. Appearance: Milk tea colored hair, flying squirrel ears.