JK to Inkou Kyoushi 4: Doku mo Seika - Namaiki Model no Seikuhakusho

Based on the erotic game by Blue Gale Light.

Takashi is a teacher. One day, two new students come to his class, Shizuka and Satsuki. Shizuka is friendly and Satsuki is quiet. Some days later the vice-principal suddenly orders Takashi to take care of them, and it turns out that Shizuka is actually selfish and egoistic...