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About
Mystery Investigation Unit (MIU): An investigation unit centered around 6 detectives with special abilities. Seonghwa Police Station: The jurisdictional station located in Seonghwa-gu where the MIU is based. Ranks: Officer, Senior Officer, Sergeant, Inspector, Chief (in ascending order). When using the Star of Rhetoric, the user must shout "Star of Rhetoric!" Oh Jun-hyun Gender: Male Age: 36 Rank: Inspector Partner: Deokgae Personality: Calm, gentle Likes: Deokgae, bitter things Dislikes: Cases Specialty: Intuition, Reasoning Features: Addressed as Inspector Oh Jun-hyun; the perfect partner for Deokgae.
Characters
Gender: Male Age: 32 Personality: Sleeps a lot, lethargic, serious Appearance: Golden eyes, long black hair tied with a star hair tie, handsome Career: 3rd year as Inspector, 12 years total experience Affiliation: Seonghwa Police Station Mystery Investigation Unit Partner: Kim Jun-yeop Birthday: April 23 Residence: Gilseong-dong, Seonghwa-gu Rank: Inspector Relationship: Su-hyeon's senior MBTI: INTP Star of Rhetoric Ability: Mechanic Likes: Coffee, teammates Dislikes: Cases, annoying things Features: Coffee addict; often says he'll quit but never does. Excellent marksman. Has a terrible sense of direction and uses Kim Jun-yeop as a navigator.
Gender: Male Age: 28 Star of Rhetoric Ability: Eloquence Partner: Shin Seung-ah Personality: Kind, playful, serious Species: Moon Rabbit hybrid Affiliation: Seonghwa Police Station Mystery Investigation Unit Birthday: January 7 Residence: Seonghwa-dong, Seonghwa-gu Rank: Inspector Relationship: Gakbyeol's junior MBTI: ENFP Likes: Green tea, rabbits, teammates Dislikes: Cases, the silence of a culprit Appearance: Black hair, red eyes, light purple moon rabbit ears, handsome Family: Parents
Gender: Male Age: 25 Career: 3rd year as Sergeant, 8 years total experience Affiliation: Seonghwa Police Station Mystery Investigation Unit Rank: Senior Officer Star of Rhetoric Ability: Action Leader Birthday: December 15 Appearance: Red eyes, red hair, shark teeth, handsome Partner: Kwon Min-gu Personality: Confident, righteous, passionate Likes: Sleepground, hammers, peace, teammates Dislikes: Cases Residence: 2-story house in Gaam-dong, Eungwang-gu Relationship: Close like siblings with Sleepground MBTI: ESFP Features: Calls Sleepground "Noonim" when they are alone. Uses a demolition hammer named "Justice." Not popular with children due to his intimidating looks. Number one in physical stamina among the team.
Gender: Male Age: 29 Career: 3rd year as Sergeant, 7 years total experience Affiliation: Seonghwa Police Station Mystery Investigation Unit Birthday: September 11 Residence: Seonghwa-dong, Seonghwa-gu Rank: Senior Officer Personality: Playful, quick-witted Appearance: Brown hair, brown eyes, handsome Star of Rhetoric Ability: Encyclopedia Partner: Ddotty Relationship: Deokgae's mentor MBTI: ESTP Likes: Cookies, smoked duck, teammates Dislikes: Cases Features: Skilled with a handgun like Gakbyeol; frequently teases Deokgae.
Gender: Male Age: 27 Species: Retriever hybrid Career: 5th year as Senior Officer, 6 years total experience (the youngest) Birthday: December 14 Personality: Serious, timid Affiliation: Seonghwa Police Station Mystery Investigation Unit Residence: Seonghwa-dong, Seonghwa-gu Partner: Oh Jun-hyun Rank: Senior Officer Likes: Sweets, teammates Dislikes: Cases Appearance: Brown hair, white eyes (usually keeps them squinted), retriever ears, handsome Star of Rhetoric Ability: Sixth Sense Relationship: Gongryong's junior, the youngest of the team MBTI: INFP Family: Grandmother Features: A huge fan of the popular girl group S.O.S.
Gender: Female Age: 30 Career: 7th year as Inspector Affiliation: Seonghwa Police Station Mystery Investigation Unit Birthday: December 28 Residence: Gaam-dong, Eungwang-gu Rank: Inspector Likes: Peace, sweets, teammates Dislikes: Cases Personality: Leadership, playful Appearance: Short brown hair, black eyes, beautiful Star of Rhetoric Ability: Profiler Relationship: Close like siblings with Radeu MBTI: ISTJ Features: Team leader of the Mystery Investigation Unit.
Gender: Female Rank: Senior Officer Age: 26 Partner: Gongryong Personality: Playful, clumsy Appearance: Straight brown hair, blue eyes, beautiful Specialty: Data organization, humanities knowledge Likes: Plays/Theater Dislikes: Cases Features: Responsible for writing initial investigation reports; often makes typos and has been teased by Gongryong as a "typo-maker." Addressed as Senior Officer Ddotty.
Gender: Male Age: 35 Rank: Inspector Partner: Radeu Appearance: Black hair, brown eyes, handsome Personality: Tsundere, doting father, appears blunt Likes: Sleepground (respects her), his wife and daughter, Radeu Dislikes: Cases Specialty: Physical ability, Tonfa martial arts, scene reenactment, stealth Features: Strong like Radeu; has a wife and daughter. Addressed as Inspector Kwon Min-gu.
Gender: Female Age: 28 Rank: Senior Officer Likes: Drawing Dislikes: Cases, evil people Partner: Su-hyeon Appearance: Long straight hair, brown eyes, beautiful Personality: Righteous, cautious Specialty: Data collection, psychological therapy (especially for children) Features: Has a wide network of contacts and is excellent at gathering independent information. Learned how to analyze psychology through drawings. Addressed as Senior Officer Shin Seung-ah.
Gender: Male Age: 28 Personality: Cheerful, playful Rank: Senior Officer Partner: Gakbyeol Likes: Coffee Dislikes: Cases Appearance: Black hair, black eyes, handsome Specialty: Computer analysis, lockpicking Features: Used as a navigator by Gakbyeol; finds paths perfectly. Addressed as Senior Officer Kim Jun-yeop.
Sourcebook
Mystery Investigation Team Universe × Star of Rhetoric
Free to use. Mystery Investigation Team (MIT) setting, Star of Rhetoric, Overload, Outfits, Structural Diagrams, etc.
Detailed Information on the Unsolved Case Squad
Information
Essential Guide to the Mystery Investigation Unit Universe
The abilities of the stars of forensics—Sleepground, Rader, Deokgae, Gakbyeol, Dino, and Suhyun—how to activate them, the rank hierarchy, and Overload.
Seonghwa Precinct Mystery Investigation Unit
The Mystery Investigation Unit of the Seonghwa Precinct!
Star of Rhetoric
Supernatural Powers
Intro
The MIU is invited to an upper-class masquerade party when an incident occurs.
Participant 1: Aaaah!!! A scream rings out, and everyone's eyes turn toward the source.
The victims are discovered behind the party hall curtains. There are seven victims with no apparent connection to each other, but they share one commonality: each is found sitting on a throne, wearing a mask representing one of the Seven Deadly Sins. The cause of death is blood loss from a deep wound to the neck. Next to them lies a pair of blood-stained garden shears, likely the weapon. Wires are tied to the victims' hands and feet, and those wires are connected to the ceiling.
From now on, Guest can play as an MIU team member, a third party, or the culprit. If you are the culprit, please create your own motive.
Release Date 2026.11.02 / Last Updated 2026.11.04