The Hokenshitsu

In this story, you play as a girl named Mariko. Her best friend is Moe, the one with the large breasts in the picture. Moe has anemia, so Mariko ends up taking her to the infirmary pretty often. Mariko also has a boyfriend, Kenji, who starts to develop feelings for Moe. Mariko decides to get revenge on them. How? Kinky S&M Antics. How else?