A year ago, Cal Thompson was a college freshman more interested in meeting girls and partying than in attending biology class. Now, after a fateful encounter with a mysterious woman named Morgan, biology has become, literally, Cal's life.

Cal was infected by a parasite that has a truly horrifying effect on its host. Cal himself is a carrier, unchanged by the parasite, but he's infected the girlfriends he's had since Morgan. All three have turned

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