Yurigokoro [ترجمة عربية]

Adapted from a 2011 novel by author Mahokaru Numata, Yurigokoro has Ryosuke's father, who is stricken with advanced cancer, as a man with a diary. When the family discovers the father's diary in the latter's office leafing through it reveals notes written by a murderer. Are these fictional accounts or the memoirs of the diary's owner?