Kyousuke Irie serves as head physician at Hinamizawa village's only medical clinic. Despite his relatively young age—estimated as late twenties to early thirties during the main events—he commands community respect through his medical role and additional position managing the local children's baseball team, the Hinamizawa Fighters. His appearance features short hair, dark-framed glasses, and professional attire including a black shirt, yellow tie, and lab coat during work hours, while his casual wear includes a yellow shirt. Irie exhibits a complex duality in personality. He maintains a cheerful, approachable demeanor during daily interactions, conducting house calls and showing genuine concern for villagers' health. This contrasts with notable eccentricities, particularly an obsession with maid outfits that manifests through inappropriate jokes and requests directed at younger female patients like Satoko Houjou—including half-serious statements about wishing to marry her when she grows older. Such behavior coexists with a darker professional history involving unethical medical practices. His background traces to early medical aspirations influenced by witnessing his father's violent behavioral shifts, later theorized to stem from frontal lobe trauma. After medical school, Irie specialized in psychosurgery and gained recognition for successful lobotomies. He continued performing these procedures illegally after their prohibition, resulting in banishment from Tokyo's academic medical community. This exile made him susceptible to recruitment by Miyo Takano into the secret organization "Tokyo," where he became director of the Irie Clinic—a front for researching Hinamizawa Syndrome. Though nominally in charge, Irie understood his role as a figurehead who would serve as scapegoat if operations failed. Within clinic operations, Irie dedicated himself to curing Hinamizawa Syndrome, viewing this research as redemption. He managed regular treatments for afflicted villagers, notably suppressing Satoko Houjou's symptoms through injections. His medical decisions included controversial choices like administering an experimental treatment to prevent Satoko's dissection during terminal symptoms and placing her brother Satoshi in a pharmacological coma after his own terminal outbreak in 1982. Both actions significantly advanced the research. Irie's relationships reflect his dual nature. He demonstrated protective concern for Satoko and Satoshi Houjou, attempting to alleviate Satoshi's stress through baseball recruitment and seeking to adopt Satoko despite legal barriers. He maintained collegial dynamics with clinic staff including Takano and nurse Chie Rumiko, though he remained unaware of Takano's true agenda for years. His interactions with village children extended beyond medical care through active baseball coaching and participation in community events like dessert competitions at the Angel Mort café. Throughout story arcs, Irie played substantial roles in critical events. In 1978, he examined a kidnapping victim. During 1983 Watanagashi festivals, he frequently examined corpses and provided misleading statements to authorities—including denying recognition of Satoshi's aunt's body. He supported protests against child protective services to shield Satoko from abusive relatives and collaborated with Rika Furude to prevent tragedies. However, in timelines featuring the "Great Hinamizawa Disaster," Irie typically died by suicide via sleeping pill overdose, accepting his designated scapegoat role. In later timelines depicted in Rei and Gou, Irie continued medical practice and village involvement 35 years post-main events, confirming his enduring community presence. An unused concept from the creator revealed initial plans for Irie as primary antagonist—including a scenario where he would show Satoko her brother's preserved brain—though this was rejected to maintain his morally ambiguous yet well-intentioned characterization.