Yoshikazu is a recurring antagonist in the Corpse Party series. He is the son of Principal Yanagihori of Heavenly Host and as such worked there with his father. His mental health deteriorated until he could not even speak due to a curse by Sachiko's mother. Yoshikazu was a kindhearted man who worked at Heavenly Host and generally got on well with the students before he became Sachiko's puppet. He helped Sachiko perpetrate the murders of 1973 before he took his own life. Even in death, he can be found roaming the halls of Heavenly Host looking for people to kill as Sachiko's pawn. A number of the corpses found inside Heavenly Host were killed by his weapon of choice, a large hammer. [From the Corpse Party Wiki]