The Occult Research Club was a group Izuko Gaen, Meme Oshino, Deishuu Kaiki, Yozuru Kagenui, and Tadatsuru Teori were a part of in college. The members studied oddities and the supernatural, though they also played a lot of shogi. Most of them supposedly shared majors.
They were also responsible for the resurrection and creation of the tsukugami who is now known as Yotsugi Ononoki. Most members have since become oddity specialists.