UNDERBOUND is set in a alternative earth in which the spirits of those who have heavily sinned roam through the it.
UNDERBOUND begins when our protagonist summons a spirit in exchange for the wish to turn his life into a much more "interesting" one. When the spirit beings killing, Japans greatest detective- Acacia, who works for her fathers government spirit investigation and elimination agency- forces him to team up with her to find and eliminate the Agony he has brought into this world.
This certain spirit seems pretty important to Acacia and her father's bloodline. For whatever reason.
