In medieval Europe, vampire legends were widespread. Anna and Lisa were sisters with a 14-year age difference. Lisa, the elder sister, had always remained youthful and beautiful, but because she took over the vampire castle left by their parents, Anna had always wanted to explore it. Lisa, however, said that Anna had to find a partner to enter the castle. Over the years, the partners Anna brought home all mysteriously disappeared after leaving breakup letters, which made Anna even more eager to see what was really inside the castle. She first drugged Lisa, then disguised herself as a castle guest, and finally informed the knights to stop Lisa so she could get in. Anna uncovered the vampires' secrets, but Leo appeared, putting the sisters in danger. In the end, after obtaining pure vampire lineage, Anna saved her sister and avenged their parents.
