Yurigokoro

Someone in this family is a killer--Ryou Azuki's manga adaptation of the best-selling novel Yurigokoro, originally written by Mahokaru Numata.

The day Ryousuke brings his fiancée Chie home to have a happy dinner with his family signals the beginning of their misfortunes. One day, he finds a notebook containing the confessions of killer in a closet in his family's house. Who wrote this diary? As he keeps on reading, the truth he arrives at is...

(Source: Futabasha, translated)