Ghost Slayer: Please let me be a human being

I just want to be a human, is that so difficult?

Aoki traveled to the Demon Slayer world, obtained the system, and honestly worked hard to improve his "professional" level. Suddenly, Muzan came to him and forced him to become a demon.

After that, he had two more goals.

First, eat the scum boss, and second, find a way to turn back into a human while retaining the power of a demon.