Movie
Description
Butt Detective is a detective whose head visually resembles human buttocks, featuring a cleft and cheeks, treated neutrally within his world. He wears his iconic beret, inherited from his father Oshiri Dandy, revealing a neatly groomed side parting underneath. He solves crimes using a highly logical and intellectually rigorous methodology inspired by Sherlock Holmes, aimed at young audiences, with a stated IQ of 1,104—a numerical play on the Japanese phrase "ii oshiri" (good butt).

He is always accompanied by his canine partner, Brown, a small brown dog often affected by Butt Detective's signature crime-solving technique: deploying potent facial flatulence, termed "fartillery" or "poot," to incapacitate criminals. This act is typically followed by his catchphrase, "Pardon me while I ‘poot’ you in your place." He frequently introduces mysteries with, "Hmm, I smell a case…". Outside work, he enjoys sweet potatoes (noted for aiding digestion) and unwinds post-case with tea, potato cakes, or long baths.

His professional history includes a long-standing rivalry with Phantom Thief U, an international jewel thief. However, narrative developments, particularly in the film *Eiga Oshiri Tantei: Star and Moon*, show a shift towards pragmatic alliance. Butt Detective collaborates with Phantom Thief U to infiltrate the Phantom Thief Academy on Stardust Island and recover the stolen Moonlight Stone from its leader, Phantom Thief G. This mission, prompted by Koala's request to find a missing idol contest participant, involves Butt Detective going undercover as an idol and reveals Brown's previously unexplored backstory.

Originating in a 2012 Japanese picture book by Troll, the character expanded into a multi-media franchise including books, television anime, films, stage musicals, video games, and merchandise. While core traits—calm demeanor, reliance on logic, and distinctive physicality—remain consistent, later installments see him navigate complex conspiracies like the Dark Age Plan and form unexpected partnerships against evolving criminal threats.