When he returns to Earth to attend the wedding of his friend in Saipan, Musashi meets a beautiful girl named Shau who claims to come from the bottom of the sea. Just then, Monster Scorpis reappears in the sky above the island and Musashi faces the monster in order to protect the girl. What is the girl's true form? And what is the strange shadowy form that follows the monster Scorpis?

It has been three spring-times since Belldandy came to Earth to grant Keiichi one wish. Things seem to be fine with them while living in the temple with Belldandy's sisters Urd and Skuld, but little do they know that a fallen god from Belldandy's past has escaped from his lunar prison. He has plans for everyone which do not include what the goddess and her human lover wanted for themselves.