Watching my precious girlfriend forced by DQN classmates using aphrodisiacs fall into degradation, I get an erection. Arata Arina.

The protagonist manages to start a relationship with Arina. A perfect 10 childhood friend and dream girlfriend. However, some bullies from school get in his way, and they manage to gangbang her plus film a video. Our good man sees such a video and begins to experience many mixed feelings. Seeing his beloved girlfriend get defiled makes him sad and furious, but the erection on his pants tells the ultimate truth: He wants to see the world burn and his girlfriend destroyed even harder. In a heartbreaking ending, the protagonist apologizes to Arina for his scummy true nature (cuckold). And she sheds a tear…