"Kamisama no Inai Nichiyoubi," also known as "Sunday Without God," is a Japanese light novel series written by Fuyumi Ono. The story is set in a world where God has abandoned humanity, resulting in a peculiar situation where people no longer age or die. This leads to a society filled with the undead and those who seek to understand their existence. The protagonist, Ai Astin, is a young girl who takes on the role of a gravekeeper, responsible for helping the deceased move on. Throughout her journey, she encounters various characters, including Hampnie Hambart, who challenge her beliefs and force her to confront the meaning of life and death in this unusual world.