Wo Zai Mojie Dang Fulu

Demons have conquered humanity, and Ichiya, along with his childhood friend Taozi, is captured and taken to a demonic realm where humans are forced into labor, experimentation, and consumption. Using his intelligence, Ichiya navigates challenges posed by the four main demon lords and secures the protection of the demon queen Monqier. However, this protection comes with a demand: he must develop a romantic relationship with her.