This anime is based on a horror novel under the same name. It starts with a student who transfers to a school in some town of Japan. His father is an archaeologist so he does not live with him and his mother is dead. He is living with his aunt and grandparents. In school he notices that there is a girl that seems odd and nobody seems to know anything about her. In fact everybody says she does not exist. Curious of what is going on he will get into serious problems as he finds out people around his classmates are dying in horrible and rare ways. He will find out a big secret within that school and so will you! This anime is great. I liked it a lot because the plot is intriguing and with suspense. Also I like the gore side of it. I hope this turns on your curiosity and you go check it out!
Video Clip (Gore)
Opening
Ending
Trailer