Based on the erotic game by Pin-Point.

Sayaka is a beautiful girl you find in every city. Most people see it with an innocent look. There was one guy who imagined him pleading with a tearful face and being aroused. Then the guy stalks the girl, and finally finds out that the girl is a whore. Finally a DVD was sent to the girl's house.
A few days later, the person who sent the DVD requested a request "I know who you are, I want an amateur to do nasty stuff with me". A Drug is given. Drugs that are used to make video gathering. Sayaka lives only for the Drugs. She begged and pleaded for another Drug.

(Source: Nekopoi and Has Been Translated)