|Japanese Name||下口 房|
|Manga Debut||:re Chapter 1|
Shimoguchi is shown to have a tall, lean build with very little excessive body fat. He has short dark hair which is slightly quiffed upwards with a receding hairline. His face is long with a wide jaw and flat facial features. His most recognizable feature is his very large, full lips. In one instance, Haise Sasaki thinks of Shimoguchi in that his lips are depicted as being much larger than they are in actuality, they were most likely drawn this way for comedic effect or to emphasize Sasaki's spite for him.
As a ghoul investigator, he comes off as quite dedicated to his work, but seems to be somewhat of a bigot; as seen when he ridiculed and embarrassed Sasaki for being unable to control his Squad members independently. Shimoguchi is also prejudicial against the Quinx Squad as a whole. However, he was gloomy and expressed grief when his subordinates were slaughtered by Black Rabbit.
Shimoguchi is first seen when Sasaki and Mutsuki decided to consult him about the whereabouts of Shirazu and Urie. Instead of giving them any information on the Torso Investigation, Shimoguchi embarrasses Sasaki for not being able to control his Squad members independently, telling him that he was not fit to be an investigator in the first place.
Later on during a meeting held among Team Mado, Hirako's Squad and Shimoguchi's Squad; Shimoguchi ignited a quarrel with Sasaki, and much to his dismay, he was forced to work in collaboration with the Quinx Squad on the Torso Investigation instead.
After Torso's true identity had been exposed, the Shimoguchi Squad visited Torso's home to scrutinize his victims and acquire some secret information of taxi recordings. Moments later, it was reported that the SS rated Rabbit of Aogiri Tree attacked and killed all the squad members, leaving Shimoguchi as the only survivor, though critically injured.
Shimoguchi is then seen in the hospital, sulking over the loss of his underlings. He told Akira to leave his get-well gifts, but later agreed to tell her everything that happened while at Torso's home.
Stumbling across Roma and recognizing her as a remnant of the clowns, he warns Rank 1 Shibashi to keep his distance. He is however disregarded by the young investigator, who believes that the "subordinate killer" Shimoguchi's time is over and is the new generation's turn to shine, only to get killed by Roma instantaneously. Along with Hirako, Shibashi, and his own squad, they engage combat with the clown before Uta shows up as well.
Rose Extermination Edit
Shimoguchi is seen raiding the Lunar Eclipse building, being 10 minutes earlier than the Quinx squad to arrive. His squad stumbles upon a Ghoul that seems to resemble Noro and decides to exterminate it as a team, proceeding cautiously. Before being able to finish announcing his statement to exterminate the ghoul completely, the masked individual swiftly cuts off his left arm and four of his right hand's fingers. Coming to terms to his inevitable death, Shimoguchi tells his new subordinates that he hates them so they would leave him behind to escape, but is instead told that he is liked by them before being killed altogether.
At his dying breath, Shimoguchi thinks back of his past on how he used to play with a certain boy named Yamagawa, but can't remember why they stopped interacting. He believes that it is because of his unattractive face and introverted nature that caused her mom pain; he wonders what his mother would do if he dies. He is then decapitated by a crazed Kanae in the aftermath and described as a beautiful rose. 
- In the CCG reports of the Auction Mopping-up Operation attached to the chapters, he's associated with "(sense of) duty" (義理).
- Despite believing himself to be ugly, ironically, Kanae in a crazed state of mind referred to him as a beautiful rose.