Toki Karaito, the protagonist, is helping out at the shrine where her grandfather serves as priest. While cleaning the shrine grounds, she hears the cawing of crows echoing around him. Toki senses something is wrong and goes to check it out, only to find four or five crows circling something. At the center of the crows' noisy buzz was a black egg and a small box! The crested ibis picked up the black egg as if to hold it to protect it from the crows. A moment later, she slips down the stairs. Later, when she regained consciousness, she found herself in a strange room. And there was a person with chemo-ears and a tail... Toki has been transported to another world where ghosts and monsters live.