Higurashi no Naku Koro ni (右代宮 戦人, Higurashi no Naku Koro ni, lit. When the Cicadas Cry) is a book written by Kuraudo Ooishi and Mamoru Akasaka. The book is meant as a sort of memoir about the serial murders in Hinamizawa as well as the investigation into those murders. The only known excerpt from the book is the ending:
Why did this tragedy occur?
Ooishi Kuraudo - Akasaka Mamoru