Seishin is the local priest in Sotoba, as well as an author in writing novels. His latest work is called Shiki, which translated in English is called Corpse Demon. He has a sense of the supernatural and detects the presence of the real "shiki." He is childhood friends with Toshio Ozaki and Mikiyasu Yasumori. He is 32 years old, single, and once attempted to commit suicide in a drunken state during his university days.