BLOOD THE LAST VAMPIRE | Episode 1

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Teropterids are evil beasts which pose as humans and live only to drink human blood. Fortunately for the human world there are groups dedicated to destroying them. A brooding and mysterious girl named Saya is the best teropterid slayer there is, and now, in 1960's Japan, she is sent to a U. S. army base which may be infested...

(Source: Anime News Network)