Lip Service summary:

Chihara is an ordinary private high school teacher who only gets laid with men. One day, a mysterious man named Jenny, who claims to be a vampire prince, appears at his door. Jenny demands that he suck the semen (energy) out of his cock in exchange for drinking his blood. Chihara is perplexed, but his sexual desire and appetite match, and they end up living together... This double feature includes "Erotic Germania Princess," which depicts the funny life of these two people living together, and "Papa to Scandal," which describes the secret pure love between a reluctant middle-aged policeman and a popular model!