Mushitarō Orugi

Appearance Mushitaro is a young man with dark hair slicked over to the left of his forehead. The pupils of his yellow eyes consist of several rings. He is very expressive. He dresses sharply, wearing a neat, green, fitting suit accessorized with a black bowtie and a pocket square.

He also had a former physical appearance, where his face was changed[3] presumably upon being a captive by The Seventh Agency

Personality Mushitaro is a somewhat stuck-up man who takes pride in his ability. He is not a particularly loyal member of the Rats, saying that it only serves to fulfill his own goals. For example, when he met Fyodor Dostoevsky, he demanded a base of operations all for himself, including a bookshelf with occult books and fine china tableware.[3] He is a formidable opponent against Ranpo Edogawa due to his ability. However, he easily breaks when his old friend Yokomizo is brought to mind, even losing interest in the outside world since his friend's death.

He is interested in occult practices and occasionally blurts out sentences related to it.[4] Contrary to his mystery writer friend, Mushitaro is quite disinterested in mystery novels.[3] Nevertheless, he sometimes writes mystery stories (though he would struggle with it), thinking that he would find his dear friend appear to him during such times whenever he yearns for his company.[5] He is also quite protective of his friend's posthumous reputation to his "ultimate mystery", doing whatever it takes to preserve the public's reception towards Yokomizo's final legacy entrusted to him.

Ability Main article: The Perfect Crime Mushitaro's ability, The Perfect Crime (完かん全ぜん犯はん罪ざい, Kanzen Hanzai?), allows him to erase any evidence of a crime perfectly. It takes the form of small, invisible creatures coming out of his body and tampering with objects. It can cause even a great detective like Ranpo to get stumped. Hence, he refers himself as the infallible "detective killer".[1]

Background In the past, Mushitaro befriended Yokomizo ever since their student days. Some time later, Yokomizo acquired gastric cancer, and they occasionally met to discuss his ultimate mystery before his nearing death. The two often argued with each other, as Yokomizo usually dismissed Mushitaro's suggestions and recommendations for his work. In the end, Yokomizo thought of the ultimate mystery by having the victim (himself) and the murderer to be accomplices, thereby asking Mushitaro to soon perform the role of the killer.[6] At some point, Mushitaro was held captive by the organization called the Seventh Agency that exploited his ability in order to cover up various crimes. Later on, Fyodor managed to break into his room after killing all the guards in order to set him free.[4] In exchange for his freedom, Fyodor asked Mushitaro to help the Rats in the House of the Dead in their cannibalism strategy.Around this time, Yokomizo had finished three volumes to what would be his final work. Mushitaro visited him to complete his ultimate mystery and strangled him in the inn he was staying in. As he killed his friend, Mushitaro wept openly and caused the final manuscript to get wet with his teardrops. Upon Yokomizo's death, he grabbed the manuscript and left the inn.[6] However, realizing that forensics might analyze the ink blots and identify it as his tears, Mushitaro rushed to a nearby shop to replace the final page with the ink blot with a photocopy. He also hid the original copy somewhere in the shop to avoid it being found in his possession in case he would be searched.[3]He then anonymously sold the manuscript to Edgar Allan Poe for ¥20 million. Later, he headed to a tower with a dummy bearing a forged face, switched his shoes with it, and dropped it off the tower to instigate the falling murder case meant for Ranpo.[1][6]