Honjou Rumiko is a school teacher caught in a web of blackmail and deceit. She is caught by 2 Yakuza gang members and forced to have sex with them and their clients. Eventually they start recruiting her students and she is forced to break up with her fiance as her world turns upside-down.

She was a pretty girl you might find in any town. Most people would look and see an innocent. Not one guy. One guy imagined her begging, tearful face and got aroused.
He didn’t even realize how deep his sadist desires went. He began to stalk her. He looked for anything to feed the fantasy that she was a dirty whore. A justification. And then, a single DVD arrived in the mail.
The DVD was a secret gathering in the home of a wealthy family,
where adults helped themselves to a young girl. The young girl was Sayaka. The sex was rougher than anything he’d ever seen.
Several days later, the person who sent the DVD
made a request. “I know who you are. I want an amateur with your sort of perverse interests to do some training.”
A drug was provided. It was a drug used to make the gathering video. Sayaka lived for it. She existed to taste it.
Her hunger for the drug made her beg and plead…
The desire that marinated his sadist heart now aimed at her.
(Source: dlsite)

Based on a game by Bishop.
Toudou Miyuki and Sanada Eiji are teachers in the same school and lovers. They had decided that they would preserve their chastity until they are married. However, Miyuki is assaulted and loses her virginity to Takuya, Eiji’s step-brother. Furthermore, it doesn’t stop there as Takuya turns his attention on the other female teachers one after the other.

Kaito left his hometown with dreams to be successful, but he doesn’t have any clear ideas so he lazily lives out every day. He decides to work at a newly opened resort facility called “A LO HA”, meets various girls and has many sexual relationships.

His next target is confirmed. A sexy art teacher who looks young and cute enough to be a student. Bondage, blackmail, constant sex and humiliation. All in a days work for our hero.

Based on the manga by Akatsuki Myuuto.
Two short sex stories where it is up to the viewer to determine if the girl pretends a condition or truly has it.
Note: Bundled with the 2011-08 issue of Comic Mujin magazine.

Based on the eroge by Marine.
Makoto is an ordinary university student who often visits a nearby swimming pool to swim and watch women in swimsuits. One day, he is asked to teach Marina how to swim. It seems she can’t swim at all. While he touches her body, he gets an erection. Marina notices it, and gives him a blowjob. When he touches her vagina, she cries out in pleasure and achieves female ejaculation. His unknown erotic ability comes into bloom! Make all women—from a university student to a married woman—ejaculate with your fingers!

Based on the Doujinshi by Uran.