Corpse Party: Book of Shadows

Corpse Party: Book of Shadows is a 2016 Japanese slasher horror film about high school student Naomi Nakashima, who goes back to her elementary school where a tragedy took place to bring back her dead friends. With the help of Ayumi Shinozaki and others, Naomi uncovers a dark secret involving Sachiko's twin sister Sachi, an evil entity that has been awakened by Sachiko's ascendancy. As Naomi tries to prevent another death, she must confront the horrors of the past and face off against the vengeful spirits, including Yuuya, who is revealed to be insane and responsible for several murders.