Jung Wooyoung is a merman that wants nothing more than to go explore the land above, though he is not allowed to. He knows the dangers but it brings more excitement Choi San is a vampire prince who wants nothing more than to escape from his life, from his family. Recently, he's been finding himself sneaking out at night to go to the ocean. All is fine until one day... he falls off a rock into the deep water. As he drifts through the water, he sees something A blue... tail?