The community is plagued by a dreadful creature - a man with a fishbowl for a head. This monster attacks its victims, and the goldfish in the bowl jumps out to drink their blood. As a result, the unfortunate person is transformed into a goldfish permanently. Unfortunately, Kousuke's younger sister has fallen prey to this terror. Kousuke takes care of his new goldfish-sister as best he can but is desperate to find a way to transform her back to human.
One day, Kousuke meets a strange girl named Ringo, who dresses oddly and carries a gun. Ringo is an apprentice blood diver and tries to combat the fishbowl man by plunging into the victim's wounds with her gun. If she can save the victims in time, they won't turn into goldfish. Ringo's mentor Ichigo believes there's a way to turn goldfish back into humans, giving Kousuke hope for his sister's fate.
Although the manga was discontinued after being serialised in a magazine, it received a continuation in Comic Earth Star. The volumes also include additional short stories, including titles like Jigoku (Hell), Kappa no Shokutaku (Kappa's Dinner Table), and Onikujo (Oni Killer).
