Sinmy - are supernatural creatures that devour human souls and lead them to destruction. Long since they were imprisoned in a world of darkness. However, escaped captivity in darkness sinmy now hide among the people hiding between night and day. that,who returns them to the world of darkness - the keeper. This is - a beautiful vampire, Miyu. Larva, faithful companion Mia, remains faithful to the terrible oath. Until then, until the oath is not executed, he helps her to cope with loneliness.