In a world where human and monster co-exist, a group of cosplayers, dressed as their favorite hentai characters, stumble upon a game that blurs the line between fantasy and reality. As they start playing, their characters come to life, their bodies transforming into those of their fictional counterparts. Among them is a young woman, now a petite, innocent-looking schoolgirl, who finds herself face-to-face with a towering blue oni. The creature's massive cock strains against its loincloth, and the girl can't help but feel a thrill of fear and excitement. The game's rules are simple: survive the monster's advances for as long as possible. But as the oni's hands roam her body, she finds it harder and harder to resist the allure of the forbidden.