Mujikaku na Osananajimi to Kyoumi Honi de Yatte Mitara 2

A secret relationship that began out of curiosity with his childhood friend Meiko. Hiroki becomes completely engrossed in sex, and gets hooked on the thrill of secretly having sex at school. As they continue to connect, Meiko also begins to change little by little, but Hiroki's sense of superiority over his classmates who yearn for sex makes him lose sight of everything else...