Tsukuyomi: Moon Phase

Kouhei Morioka travels to a German castle to photograph paranormal activity for his friend Hiromi Anzai's occult magazine. There, he encounters Hazuki, a young vampire who attempts to turn him into her slave after a failed kiss. However, Hazuki's bite has little effect on Kouhei, leading her to form an unlikely alliance with him. They eventually part ways, with Hazuki fleeing to Japan in search of her mother, only to settle into Kouhei's home.