The skeletal remains of 13 children were found in what is known as the "Haikawa Residence Incident." A mysterious mark left at the scene reappears seven years later, a mysterious communal life, a suspect known as "Father", six survivors of the incident, and layers of hidden truths. The unfolding mysteries lead to an unpredictable ending, the beginning of a human suspense story. Adapted from the manga series "Furitsumore Kodokuna Shi yo" (降り積もれ孤独な死よ) written by Inoryuu Hajime (井龍一) and illustrated by Itou Shouta (伊藤翔太).