Kyousuke Irie (入江 京介, Irie Kyōsuke) is a doctor working at the Irie Clinic.
Kyousuke used to work under an unnamed neurosurgery expert and was expected to become a very successful doctor. However, he began practicing psychosurgery, a controversial form of medical practice that had fallen out of favor with the public. His support for psychosurgery led to allegations of Kyousuke being inhumane and he was effectively shunned from the medical field. Kyousuke was attracted to the Hinamizawa Syndrome project as it supported his belief that "evil" people were affected by brain diseases. After being approached by Miyo Takano, Kyousuke began to work alongside Miyo on the Hinamizawa Syndrome project. He was sent to Hinamizawa to run his own clinic as well as research the Hinamizawa Syndrome.
After dissecting a live specimen, Kyousuke manages to create an experimental cure for Hinamizawa Syndrome. He tested this cure on the terminally-ill Satoko Houjou in order to avoid being forced to dissect her. The cure was a success, though Satoko would have to inject herself with the cure daily and come in to the clinic for regular checkups. Shortly afterwards, the Tokyo government restructured and Kyousuke was told to end his research within three years.
Kyousuke appears as a young man with medium-length brown hair and green eyes. He is usually seen wearing his lab coat over taupe slacks and shirt as well as a yellow tie adorned with a tie clip. He is always seen wearing his glasses.
- Kyousuke has expressed interest in adopting Satoko Houjou.