Gakuen Saiingoku ~Kyouki to Haramase no Utage~

There's an incident that shocks the entire Japan. The majority of female students at a certain school are pregnant. The culprit has already been captured but nobody knows how he's done it. It's believed that he is a student getting revenge for bullying. What happened in 9 months after he enters the school? This is the truth of the story.