Kyouya is a teacher to Andrude Ocean School, which is also a large ocean city. Kyouya saved three years ago. Since then, she has had a secret yearning to him. Her twin sister, Yumi, an android made by their dead parents is helping Miyu fulfill her love, but her thought is wavering between Kyouya and her sister, since Miyu's memories are implanted in her...

Another story that focuses on Kyouya but with Yui, the little sister of Masumi, who were Kyouya's first love.